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

Qualification => Subject Doubts => IGCSE/ GCSE => Sciences => Topic started by: -_- on June 08, 2009, 11:51:19 am

Title: Physics
Post by: -_- on June 08, 2009, 11:51:19 am
Hey fellows, so its ending, yeah? It was such a nice session with nice and easy exams along with some challenging ones :)

I am now willing to help you and allow all of us to help each other on the last ,or before last for some people, paper-Physics Paper 1


I hope it comes easy and straight forward, any question and doubts please dont hesitate to ask them

Thanks, and i really appreciate this Forum :)


Best Wishes
Title: Re: Physics
Post by: Q80BOY on June 08, 2009, 11:57:23 am
thanks devil93, great words  ;)
Title: Re: Physics
Post by: -_- on June 08, 2009, 11:58:29 am
thanks devil93, great words  ;)
you are welcome, and thanks to you too :)

Title: Re: Physics
Post by: -_- on June 08, 2009, 12:15:43 pm
hey guys

I need help myself :)


why isn't the answer C?

(Question is in attachment, Nov08)
Title: Re: Physics
Post by: astarmathsandphysics on June 08, 2009, 12:19:05 pm
Hot air rises away from the heater and draws in cool air through the gap


B
Title: Re: Physics
Post by: -_- on June 08, 2009, 12:22:03 pm
Hot air rises away from the heater and draws in cool air through the gap


B
ohhh yaaa haha i am so stupid i just hate these silly mistake, i just don't know why i thought for second that cold air is less denser haa i hate these moments :s


THANKS ASTAR :)
Title: Re: Physics
Post by: IGSTUDENT on June 08, 2009, 12:53:56 pm
November 1999 paper 1 Question no.7 as per me the answer shld be "D" but as per ms it is "C" .can someone explain please?

Title: Re: Physics
Post by: -_- on June 08, 2009, 12:56:34 pm
November 1999 paper 1 Question no.7 as per me the answer shld be "D" but as per ms it is "C" .can someone explain please?


because there is no friction so thiss means that no energy is lost, so when this happens automatically the ball will reach THE EXACT POSITION on the other side, which here is "C"


Hope that helps
Thanks
Title: Re: Physics
Post by: IGSTUDENT on June 08, 2009, 01:01:12 pm
Does that mean the obstacle does not cause any loss of energy?
Title: Re: Physics
Post by: -_- on June 08, 2009, 01:02:16 pm
Does that mean the obstacle does not cause any loss of energy?
by obstacle do u mean the curve downwards,, if u do then no it doesnt because there is no friction which is responsible for basically all energy wastage in the form of heat sound etc.


Hope this Helps
Title: Re: Physics
Post by: IGSTUDENT on June 08, 2009, 01:04:22 pm
Got it.Thanks a lot.
Title: Re: Physics
Post by: -_- on June 08, 2009, 01:05:18 pm
Got it.Thanks a lot.
Sure, dont forget +rep ;)
Title: Re: Physics
Post by: -_- on June 08, 2009, 01:20:00 pm
As an advise buddies, since our paper 3 was before our paper 1, so ofcourse everyone has studied by his full ability for a paper 3, meaning that you are still aware of all the syllabus, especially since the paper was less than a week ago, so focus on the past papers and do as mmmuuuccchhhh as possible so you have a look at all the questions and so easliy do the repeated ones in our exam :)

Any topic you find difficult WHEN SOLOVING THE PAST PAPERS, then study this topic :)



Hope I Help

Thanks.
Title: Re: Physics
Post by: bebo26 on June 08, 2009, 01:28:52 pm
thanks aloooot of the advice devil.. really insightful...NOT!
heheheheh.. no really Thanks,, i especially suck at physics.. lookin for some more help and advice
Title: Re: Physics
Post by: IGSTUDENT on June 08, 2009, 01:35:35 pm
Thanks Devil..workin on past papers and will study topics 2mrro.
Title: Re: Physics
Post by: Christy on June 08, 2009, 02:03:28 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:10:02 pm
thanks aloooot of the advice devil.. really insightful...NOT!
heheheheh.. no really Thanks,, i especially suck at physics.. lookin for some more help and advice

hahaha thanks man :)

Sure you are always welcome ;)
LOL
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:10:26 pm
Thanks Devil..workin on past papers and will study topics 2mrro.
aha, great man, gooood luck :)
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:11:10 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
hmm...as i recall there was only ONE or max TWO repeated questions from like 2002 or 2003 i guess


Thanks, Best Wishes
Title: Re: Physics
Post by: Christy on June 08, 2009, 02:12:19 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
hmm...as i recall there was only ONE or max TWO repeated questions from like 2002 or 2003 i guess


Thanks, Best Wishes

so they are all new questions ??
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:13:56 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
hmm...as i recall there was only ONE or max TWO repeated questions from like 2002 or 2003 i guess


Thanks, Best Wishes

so they are all new questions ??
yeah, some were direct and others required soo much thinking that i actually was going to run out of time in a PAPER 1 :S


so i advise you to not only do past papers today and tomorrow, but do them on exam conditions (timing) so u can practice ;)


Good Luck
Title: Re: Physics
Post by: Christy on June 08, 2009, 02:17:04 pm
thanks alot :)  :D
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:17:54 pm
thanks alot :)  :D
sure, dont forget +rep ;)
Title: Re: Physics
Post by: Christy on June 08, 2009, 02:20:30 pm
just did  ;)  ;D
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:22:07 pm
just did  ;)  ;D
hehe thanks, u too ;)
Title: Re: Physics
Post by: crypsAnity on June 08, 2009, 02:22:16 pm
ahhh.. thanks a bunch Devil .. (hehe.. sounds so ironic .. lol ) anyways yeah ts ending isnt it! sadly the only exams i did good so far were maths p4 and bio .. =[ I stopped studying for the rest .. sighs mcqs are sorta my last hope .. yeah so InshaAllah all of us shall get 100% in our coming phy paper! =]
Title: Re: Physics
Post by: Christy on June 08, 2009, 02:23:57 pm
not to forget chem too  ;)
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:25:30 pm
ahhh.. thanks a bunch Devil .. (hehe.. sounds so ironic .. lol ) anyways yeah ts ending isnt it! sadly the only exams i did good so far were maths p4 and bio .. =[ I stopped studying for the rest .. sighs mcqs are sorta my last hope .. yeah so InshaAllah all of us shall get 100% in our coming phy paper! =]
haha yeah!!! haha lmao ironic :P

aaaah tough luck i hope ull get gd marks :)

GOOD LUCK ALL :)
Title: Re: Physics
Post by: crypsAnity on June 08, 2009, 02:29:03 pm
yeah lol chem too .. anyways phys p3 was quite easy actually .. mostly theoretical stuff.. i just dint revise stuff because thot wouldnt come =[ and sadly forgot em .. anyways so um sorta predicting phy p3s gonna be quite hard .. yeah .. with loads n loadsa elctricity!
Title: Re: Physics
Post by: -_- on June 08, 2009, 02:35:03 pm
yeah lol chem too .. anyways phys p3 was quite easy actually .. mostly theoretical stuff.. i just dint revise stuff because thot wouldnt come =[ and sadly forgot em .. anyways so um sorta predicting phy p3s gonna be quite hard .. yeah .. with loads n loadsa elctricity!
u mean p1's haha :P


yeah really and magnetism there was barely anything abt that in p3 or p6!! :s
Title: Re: Physics
Post by: hdbkiwi on June 08, 2009, 03:00:20 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
hmm...as i recall there was only ONE or max TWO repeated questions from like 2002 or 2003 i guess


Thanks, Best Wishes

so they are all new questions ??
Think about it-there are 80 questions each year, so over 10 years, there has been 800 questions-syllabus hasn't changed-that much- so of course there will be MANY repeats so just do past papers and if you do well yoiu will be GREAT  :D :D :D
Title: Re: Physics
Post by: -_- on June 08, 2009, 03:04:12 pm
i have a question ... did bio paper 1 have repeated question .... like was it papers from 1996 to 2008 ..... or wat ??

was it current repeated questions or old repeated question ??
hmm...as i recall there was only ONE or max TWO repeated questions from like 2002 or 2003 i guess


Thanks, Best Wishes

so they are all new questions ??
Think about it-there are 80 questions each year, so over 10 years, there has been 800 questions-syllabus hasn't changed-that much- so of course there will be MANY repeats so just do past papers and if you do well yoiu will be GREAT  :D :D :D
yupp haha :P


Exactly, Do As Much As You Can ;)
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:05:49 pm
hi i hv a physics questions..

"An unstable nucleus has 145 neutrons and 92 protons. It emits a beta-particle.
How many neutrons and protons does the nucleus hv after emitting the beta particle?"

its on Oct/Nov 2005, ppr 1, ques.39

Can someone please please help me???
Title: Re: Physics
Post by: astarmathsandphysics on June 09, 2009, 03:10:22 pm
hi i hv a physics questions..

"An unstable nucleus has 145 neutrons and 92 protons. It emits a beta-particle.
How many neutrons and protons does the nucleus hv after emitting the beta particle?"

its on Oct/Nov 2005, ppr 1, ques.39

Can someone please please help me???

a neutron changes into a proton so 144 neutrons and 93 protons
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 03:11:29 pm
B -  neutrons - 144 ; protons - 93

the neutron splits into = proton + electron
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:12:13 pm
y does a neutron change into a proton?
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 03:15:50 pm
when a beta particle is emitted

a neutron splits into a proton and an electron

Title: Re: Physics
Post by: astarmathsandphysics on June 09, 2009, 03:17:16 pm
y does a neutron change into a proton?

a neutron is unstable.

The proton electron combination has less energy
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:18:11 pm
ohhhh ok.
I think i get it now.  :)
Thanks!!!!
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 03:18:59 pm
welcome..
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:38:19 pm
Hey can someone tell me the answer for Oct/Nov 2007 ppr 1 ques. 8?
Nd y is it that answer?
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 03:40:04 pm
its is "C"

because u draw a perpendicular line and drop it from point C


u will notice that it has not crossed the base line and therefore it has not toppled yet
whereas it does from point A,B and D

 :)

Title: Re: Physics
Post by: astarmathsandphysics on June 09, 2009, 03:42:41 pm
Fuses

blow if there is a short cicuit. They are connected in the live wire -brown or red- on the way to the unit. Then for example when a cable inside the a electric unit touches a metqal case the case can become live and give a shock to any person touching the case. To stop this the fuse blows as soon as any live cable touches the case then current is not allowed to reach the unit.

They come in various sizes 3A, 13A for example. The fuse should not blow if there is a normal operating current flowing. If a unit demands a 3A current, fit a 5A fuse
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:43:35 pm
umm. i so sorry bt i am really bad at finding centre of mass :(
Wat is base line?? and draw perpendicular to wat? the tables?
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 03:47:41 pm
find the attached diagram

notice that the red line (perpendicular) dropped from point C  doest not exceed/ cross the blue line (base of the glass)

whereas for the rest of the points , it does

(if the perpndicular from the center of mass crosses the base line => the object topples)
Title: Re: Physics
Post by: Aishath on June 09, 2009, 03:58:08 pm
find the attached diagram

notice that the red line (perpendicular) dropped from point C  doest not exceed/ cross the blue line (base of the glass)

whereas for the rest of the points , it does

(if the perpndicular from the center of mass crosses the base line => the object topples)

OH now i get it!!!
Thank u so much!! :D
+rep for u!!!
Title: Re: Physics
Post by: sahba on June 09, 2009, 04:02:31 pm
hey guys

I need help myself :)


why isn't the answer C?

(Question is in attachment, Nov08)
yea seriously y isnt it C ??? i also dnt rly gt it . there were sme questions in this paper tht i didnt gt the answers which were given in mark scheme. too confusing n By the way smetyms markschemes answers r wrong i saw somany like tht so i cnt rly trust it in paper1
Title: Re: Physics
Post by: Ghost Of Highbury on June 09, 2009, 04:04:11 pm
Hot air rises away from the heater and draws in cool air through the gap


B

astar had explained it

 :)
hot air is lighter therefore it moves away from the heater and cool air towards the heater