ALL PHYSICS DOUBTS - POST HERE !!

[mysteryman]

winter 05 ques 31 ppr1 physics helpppppppp may Allah help u in return

remember that current always takes the path of least resistance
when S is open, all the current has to go through the resistor since there is no other path
but when its closed, most of the current will go towards S since it has less resistance
so more current will go through the lamp therefore increasing brightness

[Vin]

in those questions about the compass, where shouldnt the needle point?

and in those questions about the 4 blocks and the temperature changes are given then they ask which one has the greatest thermal capacity. what should i write?

like in: http://www.freeexampapers.us/IGCSE/Physics/CIE/2009%20Nov/0625_w09_qp_1.pdf
question 16

in those questions about the compass, where shouldnt the needle point?

https://studentforums.biz/index.php/topic,6468.msg225169.html#msg225169
https://studentforums.biz/index.php/topic,6468.msg225177.html#msg225177

and in those questions about the 4 blocks and the temperature changes are given then they ask which one has the greatest thermal capacity. what should i write?

The one having the greatest mass has the greatest thermal capacity

Q 16)
at 0*C both are solid
at 50*C both are liquid
at 100*C and 150*C Benzene is gas

so B

[Vin]

OI THE ANSWER IS 144 AND 93, NT 145 N 93... I CHECKEDDD

yea right ... .. ... .. lemme check on google

[Syed Kazim]

winter 05 ques 31 ppr1 physics helpppppppp may Allah help u in return

Question 31 the answer is A. It becomes brighter because when the switch is closed then there is another path for the current to pass through instead of the one which has the resistor.

Question 32 the answer is C. Because the voltage in a parallel circuit is the same for all components connected in parallel across the source.

[mysteryman]

and ques 32 also plzzzz

Answer A is incorrect because the current doesnt have to be the same in every circuit
B is wrong because that is a property of a series connection where all the lamps are switched on and off together
C is correct because the voltage across each lamp has to be the same as the mains voltage
D isnt right because that is another property of a series connection where one lamp can destroy the circuit

[pglasg74]

and ques 32 also plzzzz

ill help u wiht this one.. take your room as an example, whne u turn the light on, are aall the bulbs equally bright? yes they are, thats why..

vin ill give u the fuse qn.. here:

"A mains current can safely supply a current of 40 A. A hairdryer takes 2A. It is connected to the circuit by a lead which can safely carry up to 5 A.
Which fuse is best to use in the plug fitted to the hairdryer lead?"

1 A, 3 A, 50 A OR 10 A?

[pglasg74]

i dont understand questions like #20 in summer 07.. like i dont get it, isnt wavelength supposed to decrease when they enter deeper, why are they further apart? why is the answer c not b :S:S:S:S

[mysteryman]

in those questions about the compass, where shouldnt the needle point?

https://studentforums.biz/index.php/topic,6468.msg225169.html#msg225169
https://studentforums.biz/index.php/topic,6468.msg225177.html#msg225177

and in those questions about the 4 blocks and the temperature changes are given then they ask which one has the greatest thermal capacity. what should i write?

The one having the greatest mass has the greatest thermal capacity

Q 16)
at 0*C both are solid
at 50*C both are liquid
at 100*C and 150*C Benzene is gas

so B

thanks alot. one more question about the thermal capacity
can you explain why the rest are incorrect in: http://www.freeexampapers.us/IGCSE/Physics/CIE/2006%20Jun/0625_s06_qp_1.pdf  question 16

the answer is A

[Shazizzzle]

Guys, STOP! ENOUGH!

[Syed Kazim]

In Beta decay a neutron changes to a proton and an electron. The proton remains in the nucleus and the electron is emitted as a beta-particle. The new nucleus has the same nucleon number, but its proton number increases by one since it has one more proton.

[Vin]

thanks alot. one more question about the thermal capacity
can you explain why the rest are incorrect in: http://www.freeexampapers.us/IGCSE/Physics/CIE/2006%20Jun/0625_s06_qp_1.pdf  question 16

the answer is A

look at the temperature difference .. only A has a temperature rise of 2 *C .. greatest thermal capacity


others have increased by  8, 4,6 as their thermal capacity is lesser

[Syed Kazim]

Guys, STOP! ENOUGH!

 

[Ivo]

Please please can someone answer these questions:  S06 - Qs 19 and 20.

[Vin]

In Beta decay a neutron changes to a proton and an electron. The proton remains in the nucleus and the electron is emitted as a beta-particle. The new nucleus has the same nucleon number, but its proton number increases by one since it has one more proton.

hey can u explain this ??/

[pglasg74]

In Beta decay a neutron changes to a proton and an electron. The proton remains in the nucleus and the electron is emitted as a beta-particle. The new nucleus has the same nucleon number, but its proton number increases by one since it has one more proton.

alriiiiight thanksss a lot khuda jo shukr ha the samjh main achi vayo..