IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => IGCSE/ GCSE => Sciences => Topic started by: The Golden Girl =D on July 17, 2010, 09:29:08 am

Title: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 17, 2010, 09:29:08 am
Post ALL your doubts and inquiries here :)

Don't forget to mention the following ;

1. The Year and session.
2. The Question number/part you have doubt in.


It would be better if you uploaded the paper by attaching it.

Check THIS (https://studentforums.biz/index.php?topic=10274.0) for Resources =D

Thank you =)

Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Helium on July 17, 2010, 05:40:52 pm
post ur doubts here ,and someone will hopefully answer u :)

But why IG doubt now
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 17, 2010, 09:26:52 pm
But why IG doubt now

it's for the new ig students lol  :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Master_Key on July 18, 2010, 01:48:34 pm
not 4 us  >:(
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 18, 2010, 03:12:43 pm
not 4 us  >:(

nah it's for ANY IG students *not A level key ;) *
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on July 30, 2010, 05:54:05 pm
does anyone here understand the vectors about the parallelogram rule,because i have 6 igs in nov,and i need some help,and By the way guys anyone knows when will the 2010 past papers be out
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 30, 2010, 07:03:56 pm
does anyone here understand the vectors about the parallelogram rule,because i have 6 igs in nov,and i need some help,and By the way guys anyone knows when will the 2010 past papers be out

Vectors ....Parallelogram ....that's math ... u shld post that in the math Doubts thread *or just make a thread for math threads * ,and someone will sure help u :)

well i answered this Q in another thread.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on July 30, 2010, 07:11:17 pm
Vectors ....Parallelogram ....that's math ... u shld post that in the math Doubts thread *or just make a thread for math threads * ,and someone will sure help u :)

well i answered this Q in another thread.
i have it in my physics book,and can u give me da link for ur solution law sama7ti  ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 30, 2010, 07:22:21 pm
By the way i sent u 2 msgs abt this.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 30, 2010, 07:52:21 pm
I'm sure u know forces and it's meaning but i just want to make sure u kno following :

when two forces act in the same straight line (nasf il itijah ..... mithil 2ai parallel lines )  then u get the resultant force by adding the two forces.

but as for the parallelogram , the resultant force is the diagonal of the parallelogram ...here is the rule from my book :


Oh sure thing np ..wait a sec so that i get the book.

In my book it says :

if the two forces acting at a point are represented in size and direction by the sides of a parallelogram drawn from the point ,their resultant is represented in size and direction by the diagonal of the parallelogram drawn from the point.

I hope u got it , if u didn't let me kno.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 30, 2010, 08:16:15 pm
mm i hope u saw this .
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on July 31, 2010, 10:05:52 am
I'm sure u know forces and it's meaning but i just want to make sure u kno following :

when two forces act in the same straight line (nasf il itijah ..... mithil 2ai parallel lines )  then u get the resultant force by adding the two forces.

but as for the parallelogram , the resultant force is the diagonal of the parallelogram ...here is the rule from my book :


Oh sure thing np ..wait a sec so that i get the book.

In my book it says :

if the two forces acting at a point are represented in size and direction by the sides of a parallelogram drawn from the point ,their resultant is represented in size and direction by the diagonal of the parallelogram drawn from the point.

I hope u got it , if u didn't let me kno.



i get the part about the parallel and ones in diferent diirections,i dont get ones that are right angles to each others
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on July 31, 2010, 07:10:58 pm
Well then check this out ;)

Pg 15 in this one :

http://books.google.com/books?id=V_GzUsA5e1oC&pg=PT14&lpg=PT14&dq=Resultant+Force+%2Bparallelogram+%2BIGCSE&source=bl&ots=mUq_eFrZt1&sig=KEsGM4Ubvb_WRJ-CtjDZC6SzDH0&hl=en&ei=q2ZUTOu5F6OHOOqv9J4O&sa=X&oi=book_result&ct=result&resnum=7&ved=0CDMQ6AEwBg#v=onepage&q&f=false

http://library.thinkquest.org/11686/tutorial/full_walkthrough/parallelogram.html

I hope i helped :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on August 01, 2010, 01:34:26 pm
does anyone here understand the vectors about the parallelogram rule,because i have 6 igs in nov,and i need some help,and By the way guys anyone knows when will the 2010 past papers be out

OK I really hope this helps you. Sorry it's really scruffy and not you fault if you find it difficult to comprehend.

Just follow 1-2-3-4-5-6. I think you should get it. It's from one of the past papers that I'd used to solve a similar doubt earlier.

Past papers will be out on the 12th or the 13th of this month. That is when the results for this are out too. ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 02, 2010, 09:33:57 am
i got it now,Thanks vin
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 13, 2010, 09:25:45 pm
New doubts,i hope anyone can help me,as from the IGCSE syallbus:
1.Describe compressions and rarefactions.
2.Give an account of charging by induction
3.Recall and use simple electron model to distinguish between conductors and insulators(easy things made hard :S )
4.What are relays and capacitors used for(other than storing energy)
5.Describe the action of a transistor as an electrically operated switch and show understanding of its use in switching circuits.
6.Recognize and show understanding of circuits operating as light sensitive switches and temperature operated alarms(using a relay or transistor)
7.Explain and use the terms analogue and digital.
and the whole 4.5 section except c.

Hope anyone can help,and thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 13, 2010, 09:27:14 pm
New doubts,i hope anyone can help me,as from the IGCSE syallbus:
1.Describe compressions and rarefactions.
2.Give an account of charging by induction
3.Recall and use simple electron model to distinguish between conductors and insulators(easy things made hard :S )
4.What are relays and capacitors used for(other than storing energy)
5.Describe the action of a transistor as an electrically operated switch and show understanding of its use in switching circuits.
6.Recognize and show understanding of circuits operating as light sensitive switches and temperature operated alarms(using a relay or transistor)
7.Explain and use the terms analogue and digital.
and the whole 4.5 section except c.

Hope anyone can help,and thanks

I'll iA help u but i srsly gotta gimme sometime , k ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 13, 2010, 09:28:26 pm
thanks golden girl,may i know which grade r u moving to
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 13, 2010, 09:32:03 pm
thanks golden girl,may i know which grade r u moving to

5alasit il IG Alhamdulilah ....O once  school starts ra7 koon an AS student iA :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 13, 2010, 09:51:16 pm
5alasit il IG Alhamdulilah ....O once  school starts ra7 koon an AS student iA :)
same here :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 13, 2010, 10:15:54 pm
1.Describe compressions and rarefactions.

1.the only waves that have compressions and rarefactions are Sound Waves .

Compressions : is the region when particles  are closer than normal and are at a higher pressure than Normal.

Rarefactions : is the region where particles are farther from each other and are at a lower pressure than normal

this al the info i got

2.Give an account of charging by induction

1.it occurs due to the movement of free electrons of a conductor from one side to the other under effect of an outside charge . An Opposite Charge is always formed towards the charging body .Notice that no net changed is produced in the conductor ; when the charging body is removed , the conductor becomes uncharged .

O3indi hina 9oora ....fiha a Positively charged Rod foog ......Wi an Uncharged Body mithil a Paper ....

i.e lamma ana jubt il positively charged ROD jamb il Uncharged Object ..the Uncharged Object was attracted to the ROD ..fa the side next to the ROD had  electrons (-vely chrged) ...wil jiha ilba3eed min ilROD is positively Charged ....... if u wanna remove il positively charged u'll use smthn else called *EARTHING* ..ili huwa wire connected to earth wich will nuetralise il +vely charged side of the Paper .

I hope u got , it's simple ..don't worry :)

3.Recall and use simple electron model to distinguish between conductors and insulators(easy things made hard :S )


1. wallahi hadi madri ...Bas i remeber an Experiment from maybe 8th grade or smthn ...here it is :

3indi fi i9ura .....a Rod ..half of it is made of Wood and the other half is made of Brass *ili huwa a kind of metal* .......and there is a paper placed in the center makan ween they both materials  meet ... and then light a Bunzen Burner *Fire ..a mathc ..etc* under it ...and the paper above the brass doesn't Burn shwoin that it is a CONDUCTOR

Hope that helped :$

http://www.astarmathsandphysics.com/igcse_physics_notes/igcse_physics_notes_conduction_convection_and_radiation.html

4.What are relays and capacitors used for(other than storing energy)

Capacitors : are only used to store energy as Ex of it is ..... when u recharge ur mobile .. u insert a wire into the plug ....so ur Mobile is charging ..meaning it's storing Energy cuz it has a capacitor .......and once u detach it ...ur mobile is workin ..how come ? ..it's cuz there is a capacitor ...meaning in that case it works as an Exchange to the battery .

Relay : Well .. i got a lot to tell  uabt this ....but i guess it's too much for me to write down lol ..so i'll try my best to find u gd notes somewhere iA :)


5.Describe the action of a transistor as an electrically operated switch and show understanding of its use in switching circuits.


For this i never got a satisfying answer from any of my teachers ..so  i would say ... i only understood by answering a Q abt it i think in the June or Nov 2009 sessions .....

http://www.astarmathsandphysics.com/igcse_physics_notes/igcse_physics_notes_transistors.html

6.Recognize and show understanding of circuits operating as light sensitive switches and temperature operated alarms(using a relay or transistor)


the ones i didn't know how to answer u , ask Vin abt it ,I'm sure he'll have diagrams for a full explanation of them :)


7.Explain and use the terms analogue and digital.


the only thing i ever knew abt these two is the following :

What is the Difference between analogue and digital meters ? *

Analogue Meter shows reading by a deflecting pointer while Digital meter shows reading by Numbers and Digits.


as for the last one .....I don't have the Syllabus in my hand ..so What does it talk abt ?  ::)


Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 13, 2010, 10:46:05 pm
this site will really help u if u have more doubts ;)

http://www.astarmathsandphysics.com/igcse_physics_notes_menu.html
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 13, 2010, 11:27:26 pm
Thanks alot,don't worry i understood all,im the smartest guy in the class ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 01:14:43 am
Thanks alot,don't worry i understood all,im the smartest guy in the class ;)

Anytime ...I'm glad u did :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 01:20:15 am
Thanks alot,don't worry i understood all,im the smartest guy in the class ;)

What abt this one {and the whole 4.5 section except c.} ?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 14, 2010, 11:04:33 am
it is ac\dc motors,generators,these are the hardest things i ever studied :S
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on August 14, 2010, 11:08:04 am
it is ac\dc motors,generators,these are the hardest things i ever studied :S

HAHAHAHAHA !!!! :D

You dont know the meaning of hard. Wait till you get to A- Levels. Your gonna have a mental workout that will leave you brain dead. :P

Nah, just kidding..... or am I ? :P

To be honest, AC Generators and DC motors are hard to understand at first - you just got to find a good image to look at.  ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 11:10:35 am
it is ac\dc motors,generators,these are the hardest things i ever studied :S

I have explained a part of it to a member earlier , here u go :


D.C motor and an A.C generator. i do not understand the formula and have still not get an appropriate and concise explanation  of the magnetic fields concerning them and how the rotate continuously.

ans: 1. MOTOR changes electric energy to kinetic  while GENERATOR changes kinetic energy to electric.

2. D.c motor has got a circuit connected to it that has a battery in it while the generator has a circuit connected to it which has got anythin BUT a battery *ex : lamb or voltmeter ...etc*

3. The current in the motor is DC meaning a direct current cuz BATTERIES allow only direct current to pass ,while the generator has got somthin called slip rings which allows the wires to rotate freely in both clockwise and anticlockwise which produces an AC current .

4. You use the right hand rule for GENERATORS and the left hand rule for MOTORS
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 11:12:34 am
it is ac\dc motors,generators,these are the hardest things i ever studied :S

mafi shai isma AC/DC MOTOR !!! .......il MOTOR is DC wi bas ...lakin il generator fi minu AC o fi DC ;)

I'll try my best ot explain just gimme some time :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on August 14, 2010, 11:16:11 am
DC Motors - require a Split Ring

AC Generator - require a Slip Ring                               NOTE: You dont need to know about AC motors or DC generators.

DC Motors - Electrical Energy---> K.E.

AC Gen - K.E ----> Electrical Energy

------------------------------------------------------------------------------------------------------------------------------------

DC MOTOR - Why do you need a SPLIT RING ?

Every half turn the gaps in the Split ring are in line with the carbon brushes such that the current stops flowing. Due to its momentum the coil continues to turn until the carbon brushes have reversed contacts such that the current flows in the opposite direction.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 11:21:43 am
4.What are relays and capacitors used for(other than storing energy)

http://www.gcsescience.com/pme7.htm

types of Relays :

http://www.bbc.co.uk/schools/gcsebitesize/design/electronics/switchesetcrev1.shtml
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 11:22:27 am
Here is gd one with pics ;)

http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/motorac.html
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on August 14, 2010, 11:23:15 am
Logic gates will be DEFINITELY coming in october.

Be prepared.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 14, 2010, 03:10:44 pm
Logic gates will be DEFINITELY coming in october.

Be prepared.
thats a piece of cake,i really appreciate what you and golden girl did to help me,thanks alot,im finishing physics today,i almost finished math but i have one prob which is probility,everything else is very easy
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 14, 2010, 03:34:56 pm
Recognize and show understanding of circuits operating as light sensitive switches and temperature operated alarms(using a relay or transistor)
this is only left for me to finish phsyics,anyone can help with it :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 05:57:47 pm
Recognize and show understanding of circuits operating as light sensitive switches and temperature operated alarms(using a relay or transistor)
this is only left for me to finish phsyics,anyone can help with it :D

These might help ;

http://www.reuk.co.uk/Light-Dependent-Resistor.htm

That's all i have ^_^


Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 14, 2010, 07:54:49 pm
shkran jazeelan it really helped :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 07:56:10 pm
I'm glad then ^_^
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 14, 2010, 09:43:44 pm
By the way ....Solve  past papers bil habal ....... Especially PP6 O PP3.......like itha 7aleet min 2000 ileen 2010 ...Wallah 7aifeedak 2ikteer ... O 3omrak ma tistahuin bi PP1 .....sa7 it's Easy bas feeha tricks wi twists ;) ..... O 5aleek dayman fakir il Syllabus ;)

Gd Luck :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 15, 2010, 09:04:01 am
sure thank you,i sloved P1 & P6 of phyics from 1995-2009 :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on August 15, 2010, 09:14:24 pm
MA .....Bitawfeeg ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on August 16, 2010, 09:55:37 am
MA .....Bitawfeeg ;)
thanks same to you ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: adrian1993 on August 21, 2010, 10:16:34 pm
Well, considering the fact that M/J 2010's physics paper was more to basics stuff, I would suggest that anyone taking it consolidate their basics during revision, especially the thermometer part....it was quite unexpected, considering the fact that the previous papers were all quite focused on the later topics..
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: boulderstone on August 27, 2010, 03:24:19 pm
I'm not sure if this is the right place to put this but does anyone know the grade boundaries this year for igcse physics? I did it with edexel and the letter said i had a mark of 52 - i got an a. Thanks :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on August 27, 2010, 03:29:47 pm
I'm not sure if this is the right place to put this but does anyone know the grade boundaries this year for igcse physics? I did it with edexel and the letter said i had a mark of 52 - i got an a. Thanks :)

One moment please.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on August 27, 2010, 03:33:31 pm
Download the threshold here (http://teachers.cie.org.uk/docs/dynamic/39614.pdf)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: WARRIOR on September 09, 2010, 08:53:32 am
Hey guys

I am  doing AS physics this year , and my school is not providing us with a book to study from, they said they will just keep on giving us questions till the end of year and they will keep giving us notes to study from . So i was just wondering if there is any book i can find to study from because i really am sick of looking at the question book and not having any reference to study from and so i have to wait till i get to school to get my questions answered.

Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on September 09, 2010, 08:55:43 am
http://www.amazon.com/Physics-Advanced-Science-Robert-Hutchings/dp/0174387318/ref=sr_1_1?ie=UTF8&s=books&qid=1284019564&sr=8-1 (http://www.amazon.com/Physics-Advanced-Science-Robert-Hutchings/dp/0174387318/ref=sr_1_1?ie=UTF8&s=books&qid=1284019564&sr=8-1)

The best.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: WARRIOR on September 09, 2010, 09:00:13 am
http://www.amazon.com/Physics-Advanced-Science-Robert-Hutchings/dp/0174387318/ref=sr_1_1?ie=UTF8&s=books&qid=1284019564&sr=8-1 (http://www.amazon.com/Physics-Advanced-Science-Robert-Hutchings/dp/0174387318/ref=sr_1_1?ie=UTF8&s=books&qid=1284019564&sr=8-1)

The best.
Is it possible to find that as an E-book ( FOR FREE )?

By the way do u have that book?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on September 09, 2010, 09:03:08 am
No you cant get it for free as an e-book

http://www.amazon.co.uk/International-Level-Physics-Chris-Mee/dp/0340945648/ref=sr_1_1?s=books&ie=UTF8&qid=1284019791&sr=1-1 (http://www.amazon.co.uk/International-Level-Physics-Chris-Mee/dp/0340945648/ref=sr_1_1?s=books&ie=UTF8&qid=1284019791&sr=1-1)

Another good textbook.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: WARRIOR on September 09, 2010, 09:16:40 am
No you cant get it for free as an e-book

http://www.amazon.co.uk/International-Level-Physics-Chris-Mee/dp/0340945648/ref=sr_1_1?s=books&ie=UTF8&qid=1284019791&sr=1-1 (http://www.amazon.co.uk/International-Level-Physics-Chris-Mee/dp/0340945648/ref=sr_1_1?s=books&ie=UTF8&qid=1284019791&sr=1-1)

Another good textbook.
o well thanks anyway , i guess i have to go for some BOOK shopping later. Thanks again
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: MKL on October 06, 2010, 07:58:32 am
Anyone got good notes on Digital electronics and Waves/Light/Sound?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: AshWINNER on October 06, 2010, 09:33:39 am
Yeah some physics doubts.........
1. Sometimes they ask u 2 draw a best fit CURVE in P6, is it sposed to be a curve or a line?
2.U use the potential divider in Parallel to the appliance rite>
3. Is a VOLTAGE induced in electromagnetic induction or CURRENT? If a current is produced, then is it called an EDDY current or is are eddy currents something else altogether?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Deadly_king on October 06, 2010, 11:03:31 am
Yeah some physics doubts.........
1. Sometimes they ask u 2 draw a best fit CURVE in P6, is it sposed to be a curve or a line?
2.U use the potential divider in Parallel to the appliance rite>
3. Is a VOLTAGE induced in electromagnetic induction or CURRENT? If a current is produced, then is it called an EDDY current or is are eddy currents something else altogether?

1. Yupz.........it IS a curve passing through most if not all the plotted points.

2. Yeah........it should be in parallel.

3. In electromagnetic induction, an electromotive force (EMF) is induced. Furthermore if there is a circuit, then the induced EMF will cause a current to flow across the wires forming the circuit. This current is not known as eddy current. The latter is something more complex.

If you really need to know about eddy current then follow this link, otherwise don't worry about it.
http://www.physlink.com/education/askexperts/ae572.cfm

Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Arthur Bon Zavi on October 06, 2010, 02:45:20 pm
Hey guys

I am  doing AS physics this year , and my school is not providing us with a book to study from, they said they will just keep on giving us questions till the end of year and they will keep giving us notes to study from . So i was just wondering if there is any book i can find to study from because i really am sick of looking at the question book and not having any reference to study from and so i have to wait till i get to school to get my questions answered.

Thanks

See this too:

http://www.amazon.co.uk/Cambridge-International-Physics-Coursebook-Examinations/dp/0521183081/ref=pd_sim_b_84
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on October 08, 2010, 04:05:24 pm
I dont get the whole part about motion\acceleration\speed and so,esp P3 questions,so i hope anyone here has a summary or anything that can help me.Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on October 08, 2010, 05:02:40 pm
http://revisioncentre.co.uk/gcse/physics/graphs_of_motion.html

http://www.emagister.co.uk/gcse_physics_graphs_of_motion_courses-ec170182847.htm#programa

http://www.gcse.com/forces.htm

http://www.passmyexams.co.uk/GCSE/physics/speed_velocity.html

http://www.s-cool.co.uk/gcse/physics/forces-moments-and-pressure/newtons-laws.html

http://www.gcsescience.com/pfm37.htm



I really would like to scan my copybook cuz it has everything u need abt it but i have NO scanner T_T

Well i hope these will help u , do NOT forget if u havea doubt just post ur Q and we'll iA answer u ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: HUSH1994 on October 08, 2010, 05:23:54 pm
i will go through these websites,Thanks alot,Allah ywaf2ek ow y6awel b3omrek
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on October 08, 2010, 05:25:44 pm
i will go through these websites,Thanks alot,Allah ywaf2ek ow y6awel b3omrek

Ammen O inta Kaman :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 16, 2011, 04:21:36 pm
Need Help!
Question 6, part (a)
First variant .... i would be glad if you tell me the procedure...
and if you want the formula it is ----> refractive index= sin i/ sin r :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on January 16, 2011, 04:30:10 pm
Need Help!
Question 6, part (a)
First variant .... i would be glad if you tell me the procedure...
and if you want the formula it is ----> refractive index= sin i/ sin r :)

the refractive index is given as 1.49 in the part (b) ....and when you go back to the Image the INDEX angle is 30 degree ,and the refractive angle is UNKNOWN...use the formula as follows:

1.49 = sin 30 / sin r

sin r *1.49 = sin 30

r = sin-1 [ sin 30 / 1.49 ]

the sin-1 is done by pressing shift and then sin on the calculator ;)

and you'll get the answer =]
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 16, 2011, 04:32:56 pm
Thats easy. and i also did that way but the answer is ---> 48.2 >.<
WHY?!?!?! is that :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 16, 2011, 04:35:43 pm
And I would love to share, this with all...
These are notes i found on sf, but were faulty, incomplete and understandably and also added some of mines :D :D :D :D :D.....
Thanks  8)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on January 16, 2011, 04:39:57 pm
Thats easy. and i also did that way but the answer is ---> 48.2 >.<
WHY?!?!?! is that :)

Maybe your calculator isn't functioning ,remember what ya told me last time ? ....ya so check it ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 16, 2011, 04:45:25 pm
Answer in mark scheme is 48.2 and the answer i am getting doing that method is 19.6
>.<
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on January 16, 2011, 04:47:33 pm
thanks for finally sharing Saud :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 16, 2011, 04:50:24 pm
thanks for finally sharing Saud :D
Welcomez... but first i want answer :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on January 16, 2011, 04:57:04 pm
I can't seem to get the 48.2 to be honest o.0

I'll let someone help u.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Arthur Bon Zavi on January 17, 2011, 12:29:06 pm
n = sinr/sini OR n = sini/sinr in any form
sinr/sin30 = 1.49 OR sinr = 1.49 × sin30
48.1°

^ This is from the mark scheme.

The answer should be that found by you, because when it escapes from the prism, it will have a greater speed and therefore the refractive index will be low.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 17, 2011, 12:49:32 pm
n = sinr/sini OR n = sini/sinr in any form
sinr/sin30 = 1.49 OR sinr = 1.49 × sin30
48.1°

^ This is from the mark scheme.

The answer should be that found by you, because when it escapes from the prism, it will have a greater speed and therefore the refractive index will be low.

Can you tell me why are they multiplying, when the formula is n = sin i/ sin r :-|
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Arthur Bon Zavi on January 17, 2011, 12:53:47 pm
Can you tell me why are they multiplying, when the formula is n = sin i/ sin r :-|

Because the mark sheet says, that the candidate can take it in any form, but the reason is that which I mentioned above.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on January 17, 2011, 02:21:21 pm
Remember this::

From rarer to denser medium.

(AIR  to  GLASS)

n = sin i / sin r

...

From denser to rarer.

(GLASS  to  AIR)

sin r / sin i
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Arthur Bon Zavi on January 17, 2011, 02:22:20 pm
Remember this::

From rarer to denser medium.

(AIR  to  GLASS)

n = sin i / sin r

...

From denser to rarer.

(GLASS  to  AIR)

sin r / sin i


I was thinking the same.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on January 17, 2011, 02:23:39 pm
Remember this::

From rarer to denser medium.

(AIR  to  GLASS)

n = sin i / sin r

...

From denser to rarer.

(GLASS  to  AIR)

sin r / sin i

Thanks,
i was thinking but didnt apply :-[
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on January 17, 2011, 02:33:11 pm
I remember this question.

Yeah, Vin is correct.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on February 22, 2011, 10:34:52 am
Hmm, no one was posting in these thread, so i thought of coming up with doubts :P

When sounds refracts:
Speed: Decreases     Wavelength: Decreases     Frequency: Remains Same     

When sounds reflects:
Speed: Remain Same     Wavelength: Remain Same     Frequency: Remains Same     

When sounds diffract:
Speed: Remain Same     Wavelength: Remain Same     Frequency:  Increases/Decrease

Please correct me if i am wrong :)
Thanks :D     
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on February 22, 2011, 12:27:43 pm
Hmm, no one was posting in these thread, so i thought of coming up with doubts :P

When sounds refracts:
Speed: Decreases     Wavelength: Decreases     Frequency: Remains Same     

When sounds reflects:
Speed: Remain Same     Wavelength: Remain Same     Frequency: Remains Same     

When sounds diffract:
Speed: Remain Same     Wavelength: Remain Same     Frequency:  Increases/Decrease

Please correct me if i am wrong :)
Thanks :D     

the red part is wrong , the frequency in diffraction does NOT change
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on February 22, 2011, 12:47:39 pm
the red part is wrong , the frequency in diffraction does NOT change
but in diffraction, i think something have to be changed :P
am i correct ^ ::)

Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on February 22, 2011, 02:16:23 pm
but in diffraction, i think something have to be changed :P
am i correct ^ ::)



If speed and wavelength remains constant then why should frequency change ? It cant and doesnt change in diffraction.

Diffraction is simply the spreading of waves as it passes through/around an obstacle.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on February 22, 2011, 03:19:58 pm
If speed and wavelength remains constant then why should frequency change ? It cant and doesnt change in diffraction.

Diffraction is simply the spreading of waves as it passes through/around an obstacle.
oh ya :)

thanks :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 22, 2011, 03:09:44 pm
excuse me can anyone help me with these doubts i would really appreciate that plz explain why u choosed that answer
hope many others would also find this thread useful let;s make it for paper 1 doubts for physics ppr1
Here are my doubts:
http://www.xtremepapers.net/CIE/Cambrid ... 2_qp_1.pdf
Q 10
http://www.xtremepapers.net/CIE/Cambrid ... 4_qp_1.pdf
Q 4,11,26
http://www.xtremepapers.net/CIE/Cambrid ... 8_qp_1.pdf
Q 2,38
http://www.xtremepapers.net/CIE/Cambrid ... 9_qp_1.pdf
Q 11,
http://www.xtremepapers.net/CIE/Cambrid ... 2_qp_1.pdf
Q 18
http://www.xtremepapers.net/CIE/Cambrid ... 3_qp_1.pdf
Q 17
http://www.xtremepapers.net/CIE/Cambrid ... 7_qp_1.pdf
Q 21,30(WHY NOT C)
http://www.xtremepapers.net/CIE/Cambrid ... 7_qp_1.pdf
Q 21
http://www.xtremepapers.net/CIE/Cambrid ... 5_qp_1.pdf
Q 32,29,
http://www.xtremepapers.net/CIE/Cambrid ... 5_qp_1.pdf
Q 31
SORRY 4 TOO MANY DOUBTS Thanks IN ADVANCE  :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on March 22, 2011, 03:15:48 pm
I cant open any of the links. They are all broken.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 22, 2011, 03:37:45 pm
excuse me can anyone help me with these doubts i would really appreciate that plz explain why u choosed that answer
hope many others would also find this thread useful let;s make it for paper 1 doubts for physics ppr1
Here are my doubts:
http://www.xtremepapers.net/CIE/Cambrid ... 2_qp_1.pdf
Q 10
http://www.xtremepapers.net/CIE/Cambrid ... 4_qp_1.pdf
Q 4,11,26
http://www.xtremepapers.net/CIE/Cambrid ... 8_qp_1.pdf
Q 2,38
http://www.xtremepapers.net/CIE/Cambrid ... 9_qp_1.pdf
Q 11,
http://www.xtremepapers.net/CIE/Cambrid ... 2_qp_1.pdf
Q 18
http://www.xtremepapers.net/CIE/Cambrid ... 3_qp_1.pdf
Q 17
http://www.xtremepapers.net/CIE/Cambrid ... 7_qp_1.pdf
Q 21,30(WHY NOT C)
http://www.xtremepapers.net/CIE/Cambrid ... 7_qp_1.pdf
Q 21
http://www.xtremepapers.net/CIE/Cambrid ... 5_qp_1.pdf
Q 32,29,
http://www.xtremepapers.net/CIE/Cambrid ... 5_qp_1.pdf
Q 31
SORRY 4 TOO MANY DOUBTS Thanks IN ADVANCE  :)
The links are broken, as Ari said. Just tell us which year are those?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 23, 2011, 11:45:11 am
excuse me can anyone help me with these doubts i would really appreciate that plz explain why u choosed that answer
hope many others would also find this thread useful let;s make it for paper 1 doubts for physics ppr1
Here are my doubts:
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w02_qp_1.pdf
Q 10
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s04_qp_1.pdf
Q 4,11,26
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w08_qp_1.pdf
Q 2,38
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s09_qp_1.pdf
Q 11,
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s02_qp_1.pdf
Q 18
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s03_qp_1.pdf
Q 17
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s07_qp_1.pdf
Q 21,30(WHY NOT C)
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w07_qp_1.pdf
Q 21
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s05_qp_1.pdf
Q 32,29,
http://www.xtremepapers.net/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w05_qp_1.pdf
Q 31
SORRY 4 TOO MANY DOUBTS Thanks IN ADVANCE  :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on March 23, 2011, 12:01:39 pm
excuse me can anyone help me with these doubts i would really appreciate that plz explain why u choosed that answer
hope many others would also find this thread useful let;s make it for paper 1 doubts for physics ppr1

November 2002 Q10 ANS is D  , as the car is going upwards it gains height hence the G.P.E increases *E = mgh* , and they're telling you the car is accelerating meaning it's speed is increasing hence the K.E. increases :)

June 2004
Q11 ANS is A ,because Power=work done/time .. since they have the SAME time then we are going to look at the work done i.e the weight/energy ...and since the boys weighs more then his work done(=F*d) is more hence MORE power.

I gtg , I hope Saud helps you :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on March 23, 2011, 01:30:26 pm
2008 Winter

Question 2

Its accelerating at all points.

Question 38

Half-life = time when radiation count rate is half initial value.

Half life = time when count rate is 70. That's in between 40 and 60 seconds.

2009 Summer

Question 11

You should recognise that the setup shown is used to measure atmospheric pressure in terms of mm of mercury. If the atmospheric pressure (the pressure on the pool of mercury in the dish) is same in both cases then the mercury must rise up to the same level no matter what the thickness of the tube.

This is because you MUST get a reading where the height of the mercury in the tube HAS to be 72 mm of mercury.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on March 23, 2011, 01:32:45 pm
2002 Summer

Copper = Conductor

Wood = insulator

Copper conducts the heat away quickly from the area around the paper straight to the far end. No burning of the paper.

Wood keeps the heat from being conducted away to the far end.... paper experiences significant burning on the wood side.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 23, 2011, 05:19:13 pm
Summer 2003
17 i forgot the method, b'because i had done this long back, :-[

Summer 2007
21 is B because light rays bend(refract) when they move from 1 median to another,
As water is denser than air so the rays refract away from the normal ray.

30 is also B, as potentiometer requires 3 ways input so we eliminates A and D. About C its not correct as the current will flow through the wire because it has less resistant, and current always flow through the easiest path(less resistant) so B is correct.

Winter 2007
21 is B. It is because as B line is passing through center, if you cut the half of the above and fill it it the gap which the between of 2 trough, you will get the normal water line ( Sorry, i don't know how to explain, but this is my own theory and is Common sense ::))

Summer 2005
29 is D because as the voltmeter is always connected in parallel to the object whose voltage is to be measured.

32 is B. Its due to Variable resistor doesn't work in parallel.

Winter 2005
31 is A,
Current always flows through the easiest way, way which is of less resistance. So when S is closed, the current pass through the S part instead through resistor, so the brightness increases.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 23, 2011, 10:51:19 pm
November 2002 Q10 ANS is D  , as the car is going upwards it gains height hence the G.P.E increases *E = mgh* , and they're telling you the car is accelerating meaning it's speed is increasing hence the K.E. increases :)

June 2004
Q11 ANS is A ,because Power=work done/time .. since they have the SAME time then we are going to look at the work done i.e the weight/energy ...and since the boys weighs more then his work done(=F*d) is more hence MORE power.

I gtg , I hope Saud helps you :)

Thanks alot but what is the relation By the way weight and energy is there is a rule or smthing ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 23, 2011, 10:59:07 pm
2008 Winter

Question 2

Its accelerating at all points.

Question 38

Half-life = time when radiation count rate is half initial value.

Half life = time when count rate is 70. That's in between 40 and 60 seconds.

2009 Summer

Question 11

You should recognise that the setup shown is used to measure atmospheric pressure in terms of mm of mercury. If the atmospheric pressure (the pressure on the pool of mercury in the dish) is same in both cases then the mercury must rise up to the same level no matter what the thickness of the tube.

This is because you MUST get a reading where the height of the mercury in the tube HAS to be 72 mm of mercury.


for 2008 Winter
Question 38

Half-life = time when radiation count rate is half initial value.

Half life = time when count rate is 70. That's in between 40 and 60 seconds.

isn't 140 the background radiation ???
Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 23, 2011, 11:02:25 pm
2002 Summer

Copper = Conductor

Wood = insulator

Copper conducts the heat away quickly from the area around the paper straight to the far end. No burning of the paper.

Wood keeps the heat from being conducted away to the far end.... paper experiences significant burning on the wood side.
Thanks again :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 23, 2011, 11:13:34 pm
Summer 2003
17 i forgot the method, b'because i had done this long back, :-[

Summer 2007
21 is B because light rays bend(refract) when they move from 1 median to another,
As water is denser than air so the rays refract away from the normal ray.

30 is also B, as potentiometer requires 3 ways input so we eliminates A and D. About C its not correct as the current will flow through the wire because it has less resistant, and current always flow through the easiest path(less resistant) so B is correct.

Winter 2007
21 is B. It is because as B line is passing through center, if you cut the half of the above and fill it it the gap which the between of 2 trough, you will get the normal water line ( Sorry, i don't know how to explain, but this is my own theory and is Common sense ::))

Summer 2005
29 is D because as the voltmeter is always connected in parallel to the object whose voltage is to be measured.

32 is B. Its due to Variable resistor doesn't work in parallel.

Winter 2005
31 is A,
Current always flows through the easiest way, way which is of less resistance. So when S is closed, the current pass through the S part instead through resistor, so the brightness increases.
Thanks but plz in Summer 2005
why it is not A isn't A variable resistor too
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 24, 2011, 08:57:12 am
Thanks alot but what is the relation By the way weight and energy is there is a rule or smthing ???
weight = force  (unit for both are Newtons)
energy = work done (unit is Joules for both)

Work done = force x distance
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 24, 2011, 09:29:50 am
Thanks but plz in Summer 2005
why it is not A isn't A variable resistor too
I am not sure, but what i think is that for varying a current for a parallel lamp, potential divider is the best :-\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 24, 2011, 11:15:38 am
weight = force  (unit for both are Newtons)
energy = work done (unit is Joules for both)

Work done = force x distance
ahhhhhaaaaa omg i really forgot abt that Thanks u  :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 24, 2011, 11:19:50 am
can any one answer this ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Arthur Bon Zavi on March 24, 2011, 11:34:33 am
can any one answer this ???

The third one (by Jack) because as well as getting the time for 20 swings to occur, we get the time of one complete swing.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 24, 2011, 12:54:38 pm
ahhhhhaaaaa omg i really forgot abt that Thanks u  :D
Welcome :)
:D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 24, 2011, 11:19:09 pm
guys i feel i am not totally confident abt the variable potential divider and the potential divider circuits and the thermal heat capacity (in question posted before plz help with these doubts
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 26, 2011, 01:58:11 pm
oh i think my questions are too hard  :-[
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on March 26, 2011, 02:01:47 pm
oh i think my questions are too hard  :-[

No. Its just that its too difficult to explain such concepts via the internet.

Get your teacher/tutor to answer your doubts.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 26, 2011, 02:24:10 pm
oh i think my questions are too hard  :-[
Oh, sorry
i didn't got any notification about this thread :-\
I will reply sometime later, i am doing my business so i cannot multi task in subjects :-[
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 26, 2011, 04:43:47 pm
Oh, sorry
i didn't got any notification about this thread :-\
I will reply sometime later, i am doing my business so i cannot multi task in subjects :-[
no probs i'll be waiting 4 ur reply
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 26, 2011, 06:12:29 pm
No. Its just that its too difficult to explain such concepts via the internet.

Get your teacher/tutor to answer your doubts.

well ofcourse i didn't understood them from my teacher that why i'm asking here
just if u can help with anylinks or youtube i will really appreciate it instead of explaining them
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 29, 2011, 07:59:47 pm
i'll tryto post more easier questions for u guys to answer  ;)
well, why when we drop 3 balls one aluminum,lead, wood from a bench which has same acceleration??
1.aluminum,lead
2.lead, wood
3.aluminum, wood
4.aluminum,lead, wood
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 29, 2011, 08:44:45 pm
Anymore?
Were those clear?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 29, 2011, 10:48:25 pm
Anymore?
Were those clear?
ya Thanks they were clear now i have others hope u can help with
A man jumps from an aeroplane. He falls freely
what happens to him when his parachute opens?

1.he begins to move upwards
2.he contiues falling but at a slower speed
choose one and explain why??
thxnin advance
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 29, 2011, 10:54:24 pm
ammeter reads 2A
if lamp N removed the current in ammeter become less than 2A explain why???
sorry for poor drawing :(
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 29, 2011, 10:58:01 pm
when goalkeeper punches the ball over the bar,what happens to the ball as its bunched ??
answer says it changes both shape and direction why why ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 29, 2011, 11:18:35 pm
ya Thanks they were clear now i have others hope u can help with
A man jumps from an aeroplane. He falls freely
what happens to him when his parachute opens?

1.he begins to move upwards
2.he contiues falling but at a slower speed
choose one and explain why??
thxnin advance
2nd one because when he opened the parachute, the air resistance caused by it makes it equal to the pull of gravity. So his speed gets slow ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 29, 2011, 11:22:00 pm
when goalkeeper punches the ball over the bar,what happens to the ball as its bunched ??
answer says it changes both shape and direction why why ???
When ever force is applied to an object, it would change its shape, direction and speed.
Force always do that ::)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on March 30, 2011, 12:15:17 am
ammeter reads 2A
if lamp N removed the current in ammeter become less than 2A explain why???
sorry for poor drawing :(
I am not so sure about this one :-\
Maybe its something:
Currents gets divided into half in a parallel,
M lamp takes more current and in parallel it receive the half amount of current, while in series t consume more of current :-\
I am not sure
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on March 30, 2011, 07:11:17 pm
ammeter reads 2A
if lamp N removed the current in ammeter become less than 2A explain why???
sorry for poor drawing :(

The ammeter reads a value of 2 amps since 2 amps are 'consumed' by the two lamps.

Lets say lamp M needs 1.8 amps and N neds 0.2, thus when N is removed only 1.8 amps are supplied by the battery as only M is left.

Thus, the ammeter reads 1.8 amps.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on March 31, 2011, 12:25:05 am
The ammeter reads a value of 2 amps since 2 amps are 'consumed' by the two lamps.

Lets say lamp M needs 1.8 amps and N neds 0.2, thus when N is removed only 1.8 amps are supplied by the battery as only M is left.

Thus, the ammeter reads 1.8 amps.
Thanks for the idea but i;m soorry tht i didnot mention in my previuos posts that in the question they said that the two lamps were identical so does the same idea apply
and plz do u think that when a 2A are supplied by the battery whatever lamps was there or it depends on the resistance each lamp has ???  ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 09, 2011, 12:10:09 am
hey guys i 've been waitin fir 10 days  :-[
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on April 09, 2011, 08:16:04 am
I'm sorry but what is it that you're waiting for ? .. Please Quote your post that hasn't been answered.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Most UniQue™ on April 10, 2011, 05:51:11 pm
Thanks for the idea but i;m soorry tht i didnot mention in my previuos posts that in the question they said that the two lamps were identical so does the same idea apply
and plz do u think that when a 2A are supplied by the battery whatever lamps was there or it depends on the resistance each lamp has ???  ???

This is the question
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 10, 2011, 06:00:32 pm
ammeter reads 2A
if lamp N removed the current in ammeter become less than 2A explain why???
sorry for poor drawing :(
Lamp M and N are connected in parallel.
In parallel circuits,
1-voltage is the same across each resistance, which means if the the power supply is 2v, both lamp M and N will get a 2V supply.
2-Total current supplied by the battery is equal to the sum of currents passing through each resistance or branch of the circuit.
Which means Total current = lamp M current + lamp N current
3-Total resistance of the circuit = 1/R1 + 1/R2

When lamp N is removed, we get a series circuit,
In series circuits,
1- Total volatge = V1+v2+v3
2- Total resistance = R1+R2+R3
3- Same current flows through each resistance

Lamps M and N are identical, both need same current, e.g 1A for each
when M and N are connected in PARALLEL, current= 1+1 = 2A
When only M is connected, Current= 1A
and if M and N were connected in SERIES then Current = 1A

Hope this helps ;D ;D
If ur still facing problems, then PM me
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 10, 2011, 08:09:33 pm
Lamp M and N are connected in parallel.
In parallel circuits,
1-voltage is the same across each resistance, which means if the the power supply is 2v, both lamp M and N will get a 2V supply.
2-Total current supplied by the battery is equal to the sum of currents passing through each resistance or branch of the circuit.
Which means Total current = lamp M current + lamp N current
3-Total resistance of the circuit = 1/R1 + 1/R2

When lamp N is removed, we get a series circuit,
In series circuits,
1- Total volatge = V1+v2+v3
2- Total resistance = R1+R2+R3
3- Same current flows through each resistance

Lamps M and N are identical, both need same current, e.g 1A for each
when M and N are connected in PARALLEL, current= 1+1 = 2A
When only M is connected, Current= 1A
and if M and N were connected in SERIES then Current = 1A

Hope this helps ;D ;D
If ur still facing problems, then PM me

Thanks for u Life Saver
i'll be always wait for ur convincing for ur convincing answers ;D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 10, 2011, 08:11:52 pm
Thanks for u Life Saver
i'll be always wait for ur convincing for ur convincing answers ;D
Your most welcome
2 times " for ur convincing" ?  ;D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Ghina Ghayad on April 18, 2011, 10:18:33 pm
(I know that I am replying after a complete age, but I would like to give you a pure and simple explanation including a clumsy explanation) Ask me if you can not comprehend any of the following----)
For any heat capacity question you are required to use the equation
Heat capacity=Amount of heat gained or lost by a material/Temperature change(the final and initial temperature change)
                   =Q/tThis equation should be linked with the specific heat capacity equation which is
Specific heat capacity(c)=            Heat gained or lost by a material(Q)
                                   ---------------------------------------------------------------
                                         mass of the material(m)xTemperature change
For your question in 0625/01/M/J/03 Q17, the answer is A.As to find the highest thermal capacity for the same amount of heat supplied giving that the Q in the equation [Q/t]is constant, thus the temperature change should be the least among the 4 choices.

Incase the Q value was not constant, you should have considered the equation
Specific heat capacity(c)=            Heat gained or lost by a material(Q)
                                   ---------------------------------------------------------------
                                         mass of the material(m)xTemperature change
The highest thermal capacity can be found by choosing the smallest temperature change including the greatest Q value and though with the greatest mass as the equation----Q=cxmxT.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 19, 2011, 10:22:48 am
need help with thest doubts plz i'm not sure how todraw them:
2003 June  Q 6
2006 oct/nov Q 7(b)
2004 oct/nov Q 8
2008 june Q 7 (a)
2009 june Q 9

Thanks would appreciate any help  :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 10:56:57 am
june 2003
i will solve the others too
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 11:15:47 am
october 2006
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 11:25:53 am
october 2004
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 11:33:39 am
june 2008
srry i did a mistake, the other one was incorrect, download this one
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 11:50:16 am
last one
june 2009
 ;D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Kabab on April 19, 2011, 03:56:05 pm
Damn i am late :P
Abodi good work 8)

Anyways i needed some help too..
Explain me completely about transistor :'(
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 19, 2011, 04:10:52 pm
june 2008
Thanks a billion billion times words cannot describe ur efforts Thanks again  :D

well could u plz show me the reflection and refraction as in the glass block refraction would ocurr
 and i noticed the in the diffraction graphs u took the the same length of the gap and based on that u u drew the diffracted waves right sorryi really meant thet the the straight part of ur diffracted waves depend on the lenghth of thee gap right?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 04:22:11 pm
Thanks a billion billion times words cannot describe ur efforts Thanks again  :D

well could u plz show me the reflection and refraction as in the glass block refraction would ocurr
 and i noticed the in the diffraction graphs u took the the same length of the gap and based on that u u drew the diffracted waves right sorryi really meant thet the the straight part of ur diffracted waves depend on the lenghth of thee gap right?
about the gap, its right, if the gap length is SMALLER than the wavelength, then after passing, the waves will be circular as it is shown in 2004 question, but if the gap length is GREATER than the wavelength, then they would bend the same way i drew them ( straight lines, bend at the ends)

well could u plz show me the reflection and refraction as in the glass block refraction would ocurr
wat do u mean? didnt get u. PM me ur confusion

Thanks a billion billion times words cannot describe ur efforts Thanks again  :D
Your most welcome :)

Demonic, pm me  ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Kabab on April 19, 2011, 04:30:23 pm
A simple Question:
Increasing voltage or increasing current changes the brightness of a lamp?
Like a 230W lamp is used so
A current supply of 5A and 46V will be brighter or supply of 2A and 115V

:D
Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 04:44:11 pm
both current and voltage contributes to the brightness of the lamp.
Brightness is affected by power.
power = Voltage x current
the bulb needs 230W to work at full energy.
5x46 = 230W
2x115= 230W
in both cases, the power supplied is 230
so the brightness will be the same for both
:)
Transistor in few mins ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Kabab on April 19, 2011, 04:54:20 pm
both current and voltage contributes to the brightness of the lamp.
Brightness is affected by power.
power = Voltage x current
the bulb needs 230W to work at full energy.
5x46 = 230W
2x115= 230W
in both cases, the power supplied is 230
so the brightness will be the same for both
:)
Transistor in few mins ;)
what if 2 lamps are place in parallel to each other and battery as well. SO will the lamp glow at full brightness or half brightness.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 05:07:17 pm
what if 2 lamps are place in parallel to each other and battery as well. SO will the lamp glow at full brightness or half brightness.
well, full brightness, both of them
in parallel circuits, they will all get the same voltage, so if the battery is labelled 3V, and the lamp need 3V to work, then both will work at full brightness, because they are getting the same voltage (3V) , whereas if u connect the samp circuit in series, each lamp woud get 1,5V (if they are similar) and they both would glow at half brightness.  ;D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Kabab on April 19, 2011, 05:12:23 pm
well, full brightness, both of them
in parallel circuits, they will all get the same voltage, so if the battery is labelled 3V, and the lamp need 3V to work, then both will work at full brightness, because they are getting the same voltage (3V) , whereas if u connect the samp circuit in series, each lamp woud get 1,5V (if they are similar) and they both would glow at half brightness.  ;D
Doesn't this prove that voltage changes the brightness of lamp ::)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 05:19:09 pm
actually thats wat i said
Quote
both current and voltage contributes to the brightness of the lamp
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 05:19:43 pm
Transistor
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Kabab on April 19, 2011, 05:54:12 pm
Transistor

Thanks Abodi :D
+rep for sure :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 19, 2011, 05:58:30 pm
Your most welcome :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 21, 2011, 03:15:40 pm
sorry formy doubts again but may Allah bless u for help

JUNE 2002 2 c (i)
JUNE 2005 a why  divide the time by 2*no.of swings
NOV 2007 donotunderstand how he did yhe whole question  :'( :'( :'(
JUNE 2009 b (i)
NOV 2001
JUNE 2006 4 (a) how the boiling or evaporayion affectd by the pressure
NOv 2003 7 (d)


nowplz if u have any link abt the liquid tube thermomoeter or abt sensitivity, range, linear scale definition and how the could be improved plz [post to me soon Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 21, 2011, 04:15:58 pm
do we calculate the P.E. for example for two liquids of different denisties mixed  if know where the centre of mass of each to knw the height like here
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 21, 2011, 04:21:49 pm
j 2006 4- evaporation can happen at any temp. for boiling u need to reach the boiling point e.g water boils at 100c but it can evaporate at any temp, like room temp. how pressure affects, not sure but i will try. evaporation at any temp, means pressure can be differet, boiling for water at 100c, more pressure (in gas laws, when temp increase, pressure increase) one more point, during boiling temp doesn't change, means pressure is constant
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 21, 2011, 04:27:03 pm
nov 2007, which question??
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 21, 2011, 04:32:14 pm
nov 2007, which question??
7
Thanks may Allah bless u with v high scores for ur help  :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 21, 2011, 04:48:45 pm
nov 2007
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 21, 2011, 04:53:29 pm
nov 2007
and 1 plz
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 26, 2011, 02:32:39 pm
can any one do Question 4 may/june 2010
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 26, 2011, 03:19:29 pm
may 2010:
4a- Matt black
4b- decrease on left hand, increase on right hand.
4bii- when temp rises, pressure increases. more heat absorbed by matt black, more temp rise, more pressure, air expands, push water down.
just the keywords, u can make a sentence from them ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 26, 2011, 04:26:50 pm
may 2010:
4a- Matt black
4b- decrease on left hand, increase on right hand.
4bii- when temp rises, pressure increases. more heat absorbed by matt black, more temp rise, more pressure, air expands, push water down.
just the keywords, u can make a sentence from them ;)
many Thanks what abt here http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s10_qp_61.pdf
question 4 too sorry for unconvenience
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 26, 2011, 04:49:16 pm
https://studentforums.biz/sciences/need-help-with-a-physics-question-(important)/30/
read this. download the attachment in 3rd page first post (my post)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 26, 2011, 05:20:41 pm
https://studentforums.biz/sciences/need-help-with-a-physics-question-(important)/30/
read this. download the attachment in 3rd page first post (my post)
i got the difference 2 could this occur becuase of copires as i 've done the steps same but got diifent ansers
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 26, 2011, 05:54:36 pm
doesn't matter. as it is just experimental error.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 29, 2011, 12:03:21 am
answer this plz
edited
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 29, 2011, 04:00:11 pm
show the whole question please. voltmeter for wat? measuring the voltage of......?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: EMO123 on April 30, 2011, 04:16:11 am
answer this plz
edited

parallel to the motors
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on April 30, 2011, 09:28:22 am
answer this plz
edited


Motor A and B are in parallel and therefore they have the same voltage of the power supply and therefore it should be connected parallel to the motors.

I hope I helped.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 30, 2011, 10:11:45 am
Motor A and B are in parallel and therefore they have the same voltage of the power supply and therefore it should be connected parallel to the motors.

I hope I helped.
True.
and for the voltmeter, remeber this: VOLTMETER IS ALWAYS CONNECTED IN PARALLEL TO WHAT YOU NEED TO FIND ITS VOLATAGE.
you will never find a voltmeter connected in series, and if u found one, then in it will be in paper1, and ofc it is a wrong answer
Voltmeter in parallel
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on April 30, 2011, 10:25:32 am
True.
and for the voltmeter, remeber this: VOLTMETER IS ALWAYS CONNECTED IN PARALLEL TO WHAT YOU NEED TO FIND ITS VOLATAGE.
you will never find a voltmeter connected in parallel, and if u found one, then in it will be in paper1, and ofc it is a wrong answer
Voltmeter in parallel

Typo ?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 02:32:30 pm
True.
and for the voltmeter, remeber this: VOLTMETER IS ALWAYS CONNECTED IN PARALLEL TO WHAT YOU NEED TO FIND ITS VOLATAGE.
you will never find a voltmeter connected in parallel, and if u found one, then in it will be in paper1, and ofc it is a wrong answer
Voltmeter in parallel
check which one is right
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 02:37:44 pm
Motor A and B are in parallel and therefore they have the same voltage of the power supply and therefore it should be connected parallel to the motors.

I hope I helped.
check which one is right
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 02:38:35 pm
parallel to the motors
check which one is right
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on April 30, 2011, 02:40:15 pm
check which one is right

Listen, I'm going to give you some advice. A lot of the queries you have seem to be very very basic. If you picked up your textbook and refreshed your concepts you'd be a lot better at physics.

IGCSEs aren't ONLY about past papers.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: EMO123 on April 30, 2011, 02:43:18 pm
lolzz ari

and relina all are correct so think before it :P
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 30, 2011, 03:11:03 pm
Typo ?
yes, thanks ari  ;D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 03:23:06 pm
well Thanks for u all  but if i really have some doubts and i seek help here for some questions which i want to make sure of it is this a great issue for u guys, i know it may be easy for u so it wont take from u time to just help. this question i 've asked i knew that the voltameter is connected in parallel but the drawing  just confused  me and mark scheme donot help too so i just wanted  to make sure from u  as all of u gave what i know but no one tried to solve the problem which confusion on drawing itself not concept
anyway Thanks
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 30, 2011, 03:25:45 pm
ataachements ;)
and By the way i am giving my igcse's this may ;)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 03:28:29 pm
ataachements ;)
and By the way i am giving my igcse's this may ;)
Thanks alot me too doing may
i did it as iudrew it so mine is right
Thanks again i confirmed my answer
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 30, 2011, 03:39:23 pm
you're most welcome :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on April 30, 2011, 11:02:44 pm
also this plz i got my measurements withinthe range but my average still 7.25 while mark sceme is 7.5
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_s10_qp_61.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on April 30, 2011, 11:15:21 pm
experimental error, or just size of the paper, it is different if u photocopy or download and print, so no worries
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 02, 2011, 03:09:26 pm
experimental error, or just size of the paper, it is different if u photocopy or download and print, so no worries
Thanks :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 03, 2011, 03:14:21 pm
oct/nov 2007 Q1 plz Thanks inadvance
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 03, 2011, 03:47:54 pm
oct/nov 2007 Q1 plz Thanks inadvance

Which paper ?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: EMO123 on May 05, 2011, 04:31:16 pm
oct/nov 2007 Q1 plz Thanks inadvance
ya but which paper
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 05, 2011, 05:37:31 pm
paper 3
here http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w07_qp_3.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 05, 2011, 05:46:08 pm
paper 3
here http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w07_qp_3.pdf


Terminal velocity is when the object falls at a constant velocity... Can you infer at what time it begins falling at constant velocity ?

The ball is accelerating as long as the graph has a positive gradient, though, the magnitude of the acceleration reduces with time.

Area under the graph whilst at constant velocity (see first point).

Area under the WHOLE graph.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 05, 2011, 05:50:24 pm
Terminal velocity is when the object falls at a constant velocity... Can you infer at what time it begins falling at constant velocity ?

The ball is accelerating as long as the graph has a positive gradient, though, the magnitude of the acceleration reduces with time.

Area under the graph whilst at constant velocity (see first point).

Area under the WHOLE graph.

a(i) i wrote 4.5/5/6 but answer was different so i didnot knoww why???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 05, 2011, 06:59:33 pm
a(i) i wrote 4.5/5/6 but answer was different so i didnot knoww why???

It has to be a range.

4.2 to 6 seconds.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 05, 2011, 07:02:14 pm
It has to be a range.


unfortunately its not  :(
here is the mark scheme have a look
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w07_ms_3.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 05, 2011, 07:03:14 pm
unfortunately its not  :(
here is the mark scheme have a look
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w07_ms_3.pdf


What are you talking about ?

The mark scheme says :

Quote
ALLOW 4.2 – 6s

EDIT : Look carefully at the graph. It becomes PERFECTLY horizontal at exactly 4.2s.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 05, 2011, 07:06:56 pm
What are you talking about ?

The mark scheme says :

EDIT : Look carefully at the graph. It becomes PERFECTLY horizontal at exactly 4.2s.
oh yes sorry but do u understand why the first correct answer was 1.6-1.8 s
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 05, 2011, 11:09:54 pm
help plz
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ........ on May 05, 2011, 11:21:03 pm
Distance = area under graph

Area=1/2(10+9) * 0.6  (area of trapezium)

5.7 m
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 06, 2011, 08:36:30 pm
oct/nov 2010 varient 32 paper 3
qustion 2  ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on May 06, 2011, 08:42:01 pm
Can you post a link, please?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 06, 2011, 09:18:24 pm
Can you post a link, please?
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_32.pdf
here
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on May 06, 2011, 10:42:15 pm
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_32.pdf
here

Q 2

a) Ep = mgh = 0.15 * 10 * 0.3
= 0.45 J

b i) Always remember, Kinetic energy of any body is maximum and Potential energy is minimum at the lowest point of its motion. (revise the line)

so the lowest point of the bob is 0.1 m (o.3 - 0.2 i.e height of the bob in fig. and length of the string)
here the kinetic energy is max and p e is min.
always Ep lost = Ek gain
so Ep at this point = 0.15 * 10 * 0.1
= 0.15 J

ii) Ek = 0.5 * m * v^2
0.15 = 0.5 * 0.15 * v^2
v = 1.4 ms-1

iii) 0.3, because the bob has only that much of energy to reach to the other side, energy is not lost or gained during the system. (extra info - Then again a question arises, at the left the length of the string is "more", if you see, at the release point the length of the string is small, so the velocity with which the bob will travel to left is greater, then will slow down, so ultimately both the energies during the motion add up to give the resultant energy of 0.45 J or energy at 0.3 to the right. If you know what I mean :P )

iv) drawing is easy. they haven't ask you for a precise scale drawing.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 07, 2011, 07:55:59 am
Q 2

a) Ep = mgh = 0.15 * 10 * 0.3
= 0.45 J

b i) Always remember, Kinetic energy of any body is maximum and Potential energy is minimum at the lowest point of its motion. (revise the line)

so the lowest point of the bob is 0.1 m (o.3 - 0.2 i.e height of the bob in fig. and length of the string)
here the kinetic energy is max and p e is min.
always Ep lost = Ek gain
so Ep at this point = 0.15 * 10 * 0.1
= 0.15 J

ii) Ek = 0.5 * m * v^2
0.15 = 0.5 * 0.15 * v^2
v = 1.4 ms-1

iii) 0.3, because the bob has only that much of energy to reach to the other side, energy is not lost or gained during the system. (extra info - Then again a question arises, at the left the length of the string is "more", if you see, at the release point the length of the string is small, so the velocity with which the bob will travel to left is greater, then will slow down, so ultimately both the energies during the motion add up to give the resultant energy of 0.45 J or energy at 0.3 to the right. If you know what I mean :P )

iv) drawing is easy. they haven't ask you for a precise scale drawing.
Thanks but in b revised the graph and i think it should be   0.2
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on May 07, 2011, 11:53:56 am
Thanks but in b revised the graph and i think it should be   0.2

You're right :/

sorry, my bad.
Okay, so 0.1 is the CHANGE in height. It was 0.1 from the peg, now at perpendicular, it is 02. So delta h is 0.1
reason because when it is at the lowest position, there is still some potential energy, so we cannot take that as 0. so we have to consider the change in height, or change in potential energy.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 07, 2011, 06:25:00 pm
You're right :/

sorry, my bad.
Okay, so 0.1 is the CHANGE in height. It was 0.1 from the peg, now at perpendicular, it is 02. So delta h is 0.1
reason because when it is at the lowest position, there is still some potential energy, so we cannot take that as 0. so we have to consider the change in height, or change in potential energy.
plz we dont take it as 0.??? what
and i know that ur convined but my bad the march schme said ur previous answer is right???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Blizz_rb93 on May 09, 2011, 06:57:15 pm
I need a list of all the precautions in radioactivity
Thank You =D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 10, 2011, 01:53:29 pm
I need a list of all the precautions in radioactivity
Thank You =D
Safety Precautions:
• Keep all radioactive materials in sealed containers made
of thick lead.
• Keep as far away from radioactive source as possible
and use tongs.
• Waste radioactive products are either buried
underground or under the sea.
• Keep exposure time as short as possible.
• Don’t eat or drink near a radioactive substance.
• Label radioactive sources with radioactive sign.
• Wear a radioactive badge: Hole to detect alpha,
Aluminum to detect beta, Lead to detect gamma.
• Half-life is not affected by temperature, pressure or
chemical reactions.

Copy pasted from my notes :P
:)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 10, 2011, 02:04:28 pm
• Waste radioactive products are either buried
underground or under the sea.

That's why sea is polluted and soil is infertile!!
Sea creatures die, and plants/underground organisms die.
Idiots are ruining our planet!!
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 10, 2011, 02:41:05 pm
That's why sea is polluted and soil is infertile!!
Sea creatures die, and plants/underground organisms die.
Idiots are ruining our planet!!
Then were can we keep?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 10, 2011, 04:54:48 pm
outer space?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 11, 2011, 05:21:26 am
outer space?
wouldn't it be better to feed many hungry people, than wasting money on correct disposal of radioactive.. :-\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 11, 2011, 09:53:44 am
wouldn't it be better to feed many hungry people, than wasting money on correct disposal of radioactive.. :-\
true, but its better than making them live with mutations!!!
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 11, 2011, 10:04:41 am
true, but its better than making them live with mutations!!!

true true... but if just leave the radioactive material in the outer space what are chances if it may come back? due to gravity? :-\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 11, 2011, 10:08:40 am
true true... but if just leave the radioactive material in the outer space what are chances if it may come back? due to gravity? :-\

they will take care of it and make sure it wont come back due to gravity
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 11, 2011, 10:35:39 am
they will take care of it and make sure it wont come back due to gravity
would that be a lot expensive?
Going to space/planet to bury a small quantity of radioactive substance almost every year or half year? :-\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 11, 2011, 10:39:03 am
would that be a lot expensive?
Going to space/planet to bury a small quantity of radioactive substance almost every year or half year? :-\
yes it is!
they have to find a better way of disposal.
if i will dispose radioactive material near ur house, u wont like it.
this should be moved to the debates section
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 11, 2011, 10:56:34 am
Can we please remain on topic over here ? This thread is for Physics doubts not debating.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 11, 2011, 11:32:10 am
Can we please remain on topic over here ? This thread is for Physics doubts not debating.

yes, sorry
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 11, 2011, 08:08:05 pm
hello anybody expalin this plz
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on May 11, 2011, 09:16:57 pm
Least count = 0.01 cm
Vernier scale reading(division) = 4 (4th division's coinciding)
main scale reading = 0.10 cm (the 0th division's right after 0.1 and before 0.2, so in between two values you always take the lower value )

Total reading = main scale reading + (vernier scale division x least count)

TR = MSR + (VSR x LC)

= 0.10 + (4 x 0.01)
= 0.10 + 0.04
= 0.14 cm
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 11, 2011, 10:02:13 pm
Least count = 0.01 cm
Vernier scale reading(division) = 4 (4th division's coinciding)
main scale reading = 0.10 cm (the 0th division's right after 0.1 and before 0.2, so in between two values you always take the lower value )

Total reading = main scale reading + (vernier scale division x least count)

TR = MSR + (VSR x LC)

= 0.10 + (4 x 0.01)
= 0.10 + 0.04
= 0.14 cm

thank you very much  :D

ah i wanna ask also does this also apply for the micrometer or it does not have zero error and if itt does is it by the same method u showed to me
Thanks in advance
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 12, 2011, 09:16:34 am
Least count = 0.01 cm
Vernier scale reading(division) = 4 (4th division's coinciding)
main scale reading = 0.10 cm (the 0th division's right after 0.1 and before 0.2, so in between two values you always take the lower value )

Total reading = main scale reading + (vernier scale division x least count)

TR = MSR + (VSR x LC)

= 0.10 + (4 x 0.01)
= 0.10 + 0.04
= 0.14 cm
Good doubt relina.. and i guess micrometer and calipher are same things :-\

Vin i didn't understand :(
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Master_Key on May 12, 2011, 01:50:40 pm
Good doubt relina.. and i guess micrometer and calipher are same things :-\

Vin i didn't understand :(
Vernier Calliper.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 12, 2011, 02:17:17 pm
thank you very much  :D

ah i wanna ask also does this also apply for the micrometer or it does not have zero error and if itt does is it by the same method u showed to me
Thanks in advance

Are you sure you understand what a zero error is ?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: Vin on May 12, 2011, 03:28:45 pm
Good doubt relina.. and i guess micrometer and calipher are same things :-\

Vin i didn't understand :(

okay, there are certain methods to go about on the calculations for both the instruments.

you have to understand first WHY do you actually use those instruments rather than a regular ruler. The simple and primary reason being they provide more accuracy. There are others as well - they can calculate the diameter accurately etc.

vernier callipers (vc) and micrometer gauge (mg) are NOT the same thing however the theoretical calculation is similar.

VC has a least count of 0.01 cm so it can calculate the diameter of an object to 3 sfg.
MG has an LC of 0.001 cm
^ These are standard least counts for instruments. This can vary too.

Google the rest please because theres a lot to learn and i cannot possibly type everything because i have to go study chemistry.

http://www.tutorvista.co.uk/content/physics/physics-i/measurement-and-experimentation/vernier-callipers-animation.php

http://www.tutorvista.co.uk/content/physics/physics-i/measurement-and-experimentation/screw-gauge.php

^ These should cover pretty much everything up including the calculation for LC and zero error.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 12, 2011, 03:47:20 pm
Calculation of the least count is not a necessity to determining the zero error.

When the jaws are closed you can simply read of the scales and determine the zero error.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 12, 2011, 03:58:35 pm
okay, there are certain methods to go about on the calculations for both the instruments.

you have to understand first WHY do you actually use those instruments rather than a regular ruler. The simple and primary reason being they provide more accuracy. There are others as well - they can calculate the diameter accurately etc.

vernier callipers (vc) and micrometer gauge (mg) are NOT the same thing however the theoretical calculation is similar.

VC has a least count of 0.01 cm so it can calculate the diameter of an object to 3 sfg.
MG has an LC of 0.001 cm
^ These are standard least counts for instruments. This can vary too.

Google the rest please because theres a lot to learn and i cannot possibly type everything because i have to go study chemistry.

http://www.tutorvista.co.uk/content/physics/physics-i/measurement-and-experimentation/vernier-callipers-animation.php

http://www.tutorvista.co.uk/content/physics/physics-i/measurement-and-experimentation/screw-gauge.php

^ These should cover pretty much everything up including the calculation for LC and zero error.
oh so so sorry... i knew that thr use.. but i didn't get the calculation part :(
from where is .10, 4 and .01 coming :(
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 12, 2011, 10:55:09 pm
Are you sure you understand what a zero error is ?
i got confuded from these question by book simply says read where the scales coincide then if it + add it to ur reading now still confused by what the previous question asked
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 13, 2011, 08:31:13 am
i got confuded from these question by book simply says read where the scales coincide then if it + add it to ur reading now still confused by what the previous question asked

Normally, when you close the jaws of a vernier calliper or those of a micrometer the scale MUST show a reading of zero.

That's because its obviously measuring nothing.

However, sometimes due to callibration errors or misuse of the equipment when you close the jaws the scale DOESN'T read zero.

Instead the scale will show some value. This value, when the jaws are closed, is the zero-error of your vernier calliper/micrometer.

If you use a vernier calliper with a zero error you must do the following :

measured length as per vernier  MINUS zero error.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: curiousguy on May 13, 2011, 07:38:46 pm
can some one please answers these question of paper 1 2003,2004,2005 queation 39. And please explain me with detail how to find half life and its concept.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 13, 2011, 07:43:53 pm
can some one please answers these question of paper 1 2003,2004,2005 queation 39. And please explain me with detail how to find half life and its concept.
2003, 2004 and 2005 question 39th which one summer or winter? :-\

And about the half life, its just the half of the real life( i.e. life/2 for one half life)
Its when the material decays, Gamma decays slowest, then comes the beta and finally alpha :)
Decays meant that it's radioactivity is reduced :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 14, 2011, 03:00:44 am
http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_w02_qp_1.pdf

question 10 please.
Thanks in advance.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 14, 2011, 03:53:45 am
http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_w02_qp_1.pdf

question 10 please.
Thanks in advance.


It is accelerating hence its velocity is increasing. Thus, its KE will increase (KE = 0.5mv2)

Since it is moving upwards it is attaining a new vertical height, hence, its GPE increases.

Answer = D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 14, 2011, 11:06:44 am
https://studentforums.biz/sciences/all-physics-igcse-doubts-here-!!/210/?action=post;num_replies=217

question 11
How to perform this type of question? :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 14, 2011, 11:30:50 am
https://studentforums.biz/sciences/all-physics-igcse-doubts-here-!!/210/?action=post;num_replies=217

question 11
How to perform this type of question? :)

The link you've given isnt functioning.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 14, 2011, 11:58:05 am
The link you've given isnt functioning.
oh oh, sorry
Thats not the link, this one:
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_12.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 14, 2011, 12:24:11 pm
oh oh, sorry
Thats not the link, this one:
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_12.pdf

The reciprocal of the gradient of the graph is the spring constant since :

F=ke   ;   k = F/e

K in this case is equal to 2.5

If the spring length when the unknown weight is added is 16.4 :

F =ke

F = 2.5*(16.4-15)

F = 3.5 N
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 14, 2011, 12:46:44 pm
The reciprocal of the gradient of the graph is the spring constant since :

F=ke   ;   k = F/e

K in this case is equal to 2.5

If the spring length when the unknown weight is added is 16.4 :

F =ke

F = 2.5*(16.4-15)

F = 3.5 N
Shukran(arabic).. Thank you... xie xie(chinese)...
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 14, 2011, 01:03:26 pm
It is accelerating hence its velocity is increasing. Thus, its KE will increase (KE = 0.5mv2)

Since it is moving upwards it is attaining a new vertical height, hence, its GPE increases.

Answer = D
Thanks :)
rep
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 14, 2011, 02:09:22 pm
Can someone please explain to me how do you solve Q38 in this paper?
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_11.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: elemis on May 14, 2011, 02:16:41 pm
Can someone please explain to me how do you solve Q38 in this paper?
http://www.xtremepapers.me/CIE/Cambridge%20IGCSE/0625%20-%20Physics/0625_w10_qp_11.pdf

Every 70 seconds the count rate will half.

If you started off with a count rate of 100 the 70 seconds EARLIER the count rate would be 140.

Hence, if you have a count rate of N the count rate 70 seconds EARLIER would be 2N.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 18, 2011, 07:57:24 pm
http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_w05_qp_6.pdf
Question 2 (a)  and (C)please :)
and: http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_s06_qp_6.pdf
Question 1(d) and explain it please

help as soon as possible, my exam is 2mrw!
Thanks in advance :-*
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 19, 2011, 07:58:20 am
Every 70 seconds the count rate will half.

If you started off with a count rate of 100 the 70 seconds EARLIER the count rate would be 140.

Hence, if you have a count rate of N the count rate 70 seconds EARLIER would be 2N.

Thank you and I apologize for the late reply! :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 19, 2011, 10:01:56 am
http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_w05_qp_6.pdf
Question 2 (a)  and (C)please :)
and: http://www.xtremepapers.me/CIE/index.php?dir=Cambridge%20IGCSE/0625%20-%20Physics/&file=0625_s06_qp_6.pdf
Question 1(d) and explain it please

help as soon as possible, my exam is 2mrw!
Thanks in advance :-*
Help someone :s my exam is after 3 hours!!!!!!
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 24, 2011, 01:58:09 pm
hello plz anyone can help with the refractive index issue as i noticed that there ws a conflict between
May/June 2005 Q6
May?june 2009 Q 8
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 24, 2011, 03:21:32 pm
hello plz anyone can help with the refractive index issue as i noticed that there ws a conflict between
May/June 2005 Q6
May?june 2009 Q 8


The refractive index is different every time, it depends on the frequency of light that passes through what sort of material, it'll be given to you, or you'd have to calculate it using the formula(s) that you've learnt.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 24, 2011, 04:18:20 pm
The refractive index is different every time, it depends on the frequency of light that passes through what sort of material, it'll be given to you, or you'd have to calculate it using the formula(s) that you've learnt.
the problemis that each q asks to bring the same thing but each one used different way of refractive index one used sin(i)/sin(r)and the other used sin(r)/sin(i) even both moved from the more dense to less dense so why ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 24, 2011, 05:04:36 pm
the problemis that each q asks to bring the same thing but each one used different way of refractive index one used sin(i)/sin(r)and the other used sin(r)/sin(i) even both moved from the more dense to less dense so why ???

The correct formula that you can use in both cases is Sin i/Sin r, it's acceptable in both the questions.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 24, 2011, 05:51:48 pm
The correct formula that you can use in both cases is Sin i/Sin r, it's acceptable in both the questions.
but if u apply this in may 2009 it will not work ???
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 24, 2011, 06:31:15 pm
but if u apply this in may 2009 it will not work ???

Here's what the MS says:
n = sin i / sin r  OR  n = sin r / sin i  OR  1.49 = sin i / sin 35 C1
  (allow 1.49 or refractive index instead of n in any of above)
  58.719° to at least 2 s.f.  Allow 58.71°
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 24, 2011, 09:18:42 pm
Here's what the MS says:
n = sin i / sin r  OR  n = sin r / sin i  OR  1.49 = sin i / sin 35 C1
  (allow 1.49 or refractive index instead of n in any of above)
  58.719° to at least 2 s.f.  Allow 58.71°
i know that but plz if u measure the angles and try to put it in equation of n = sin i / sin r answer will not be 58.7
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 24, 2011, 09:23:57 pm
here is another question
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 25, 2011, 05:09:59 am
i know that but plz if u measure the angles and try to put it in equation of n = sin i / sin r answer will not be 58.7

Ohhh, I got you, yea, I get something like 22.6 - I'm sorry, I can't figure out the reason behind this, but as far as I remember when you have to find the refractive index, you use the formula, n=sin i/sin r
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 25, 2011, 10:11:24 am
Ohhh, I got you, yea, I get something like 22.6 - I'm sorry, I can't figure out the reason behind this, but as far as I remember when you have to find the refractive index, you use the formula, n=sin i/sin r
me too hope somebody help  ??? soon exam after tommoroow
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 25, 2011, 10:11:50 am
here is another question
and this one anyo ne know how to do it
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: **RoRo** on May 25, 2011, 11:36:56 am
and this one anyo ne know how to do it

Which year is this from?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 26, 2011, 06:11:46 pm
Which year is this from?
actuaaally i think at 99 or somting like that not sure
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 26, 2011, 06:59:32 pm
actuaaally i think at 99 or somting like that not sure
is the answer 1.65x10^6  ? :-\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 26, 2011, 09:57:50 pm
is the answer 1.65x10^6  ? :-\
no actually my teacher told me that answer is 1.5x10^6 but when he expalined i didnot undersatnd any thing so do u have any explanation
and also did u read the previous posts abt the conflict in applying the refractive index rule??
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 26, 2011, 10:04:38 pm
Relina, it would be better if u post the whole question, or a link to the question paper.
Could u please do it?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 26, 2011, 10:09:33 pm
Wait
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: NotAbod on May 26, 2011, 10:16:25 pm
Waiting......
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on May 26, 2011, 10:24:54 pm
no actually my teacher told me that answer is 1.5x10^6 but when he expalined i didnot undersatnd any thing so do u have any explanation
and also did u read the previous posts abt the conflict in applying the refractive index rule??
i just came in saw your question... :)
isn't it almost equal? :0\
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: ~ Miss Relina ~ on May 26, 2011, 10:29:18 pm
An error occured,the file can't be attached.
 No problem and thanks. :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: merihan on June 15, 2011, 07:19:55 pm
hey anyone having physics 2010 past paper plz tell me.......i need oct nov 2010......help!!!!!!!
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: SauD~ on June 18, 2011, 08:26:10 am
hey anyone having physics 2010 past paper plz tell me.......i need oct nov 2010......help!!!!!!!
Here:
https://studentforums.biz/past-papers/igcse-2010-winter-exam-papers/msg393501/#new

or directly jump to the site:

http://www.mediafire.com/?r7fuf3fi7sea2

:)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: lollypop on May 18, 2012, 06:35:20 pm
Oct/nov 01 p3 Q8 part b - can anyone pls help me with this question?
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: The Golden Girl =D on May 27, 2012, 02:51:49 pm
^ can ya upload it please :)
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: M.Salik on October 14, 2012, 04:35:06 pm
Hello,

I have a doubt in Pastpaper, O/N 2003 Q8a(Link is below) (How to draw a graph of output of an A.C Generator)??
Any help will be appriciated.
Thank You in  advance.

http://www.xtremepapers.com/papers/CIE/Cambridge%20IGCSE/Physics%20(0625)/0625_w03_qp_3.pdf
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: astarmathsandphysics on October 15, 2012, 04:41:59 pm
see attachment
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: skylite on May 08, 2013, 12:05:05 pm
Hi,

I have problems in understanding 'cuts magnetic flux' in electromagnetism and whats the symbol in electric circuit diagram for a Variable power supply?

Can anyone please explain? Thanks :D
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: astarmathsandphysics on November 07, 2013, 01:34:37 pm
A varible powe rupply is the symbol for a transformer.
Title: Re: IGCSE PHYSICS DOUBTS HERE !!!!
Post by: astarmathsandphysics on November 07, 2013, 01:36:05 pm
for cutting magnetic field, imagine cutting grass. The grass grows up and the blade cuts through it horizontally.