A2 Physics | Post your doubts here

[KaiserFury]

Ill reply for each one seperately cause my laptop is being uber-slow right now.

For s03 --q2 a) when water is evaporating at a constant temperature, there is no change in k.e but the molecules must overcome the intermolecular forces.. they move away from each other and so their potential energy increases. Internal energy is p.e + k.e, so internal energy is increasing if p.e is increasing.

Stretching a wire is the same story. When you stretch the wire, you make the atoms and electrons rearrange and move away from each other so the p.e increases.

Thank you so much ... Can you please answer my final question?

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_s11_qp_41.pdf
- Number 6 (b)(ii)

 

[user]

dint get you there

Oh well any advice how to study applications as quick as possible others are managable but i m still having confusion with telecommunication its so scaryyy man

ikr ..

and btw for revising pastpapers, go through the notes XPFMember uploaded...i guess they contain imp info from pastpaper questions..i gotta do that too...

 

[mr_perfect]

my preparation is very bad and i m having a high fever. please everyone pray for me so that i can score an A in Phys and Maths . please pray for me my brothers. INSHA-ALLAH i will score A in both these subjects.

 

[NyTRiDr]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_42.pdf

question 9 part 2!
i know the logic tht V1 should be equal to V2 but in order to determine V2 we'll have to calculate it through potentiometer way.. i:e R (strain guage)/R (total) * 4.5 but in mark scheme they have done opposite. they did it by R (resistor) / R(total) * 4.5.. please check and clarify,sum1!!

 

[user]

my preparation is very bad and i m having a high fever. please everyone pray for me so that i can score an A in Phys and Maths . please pray for me my brothers. INSHA-ALLAH i will score A in both these subjects.

assalamoalaikum wr wb!
sure.May Allah give u the best of health n faith..and may Allah grant u success in both worlds...may u get A starss...aameen!

 

[ousamah112]

http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s09_qp_4.pdf q9 b

 

[larina]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s11_qp_42.pdf

question 9 part 2!
i know the logic tht V1 should be equal to V2 but in order to determine V2 we'll have to calculate it through potentiometer way.. i:e R (strain guage)/R (total) * 4.5 but in mark scheme they have done opposite. they did it by R (resistor) / R(total) * 4.5.. please check and clarify,sum1!!

V+ = V- ( or V1 = V2)
We can find out V2 by this equation....
1000/(1000+125) * Vin
===>Vin is 4.5V
so 1000/1125 * 4.5 = 4V

 

[RGBM211]

ikr ..

and btw for revising pastpapers, go through the notes XPFMember uploaded...i guess they contain imp info from pastpaper questions..i gotta do that too...

OMG! thanks for reminding i am still stuck in solving past papers its like mmm revising 2 topics and doing the topical pastpapers some are from 2005-2011 and some are from 2002-2011 sigh* when will i complete everythin and maths :'(

 

[Idris]

Reduction in variation in rectified voltages

To increase the smoothing, increase the capacitance of the capacitor.

 

[arlery]

OMG! thanks for reminding i am still stuck in solving past papers its like mmm revising 2 topics and doing the topical pastpapers some are from 2005-2011 and some are from 2002-2011 sigh* when will i complete everythin and maths :'(

I'm doing the same thing! Well I still have till tomorrow morning, so not going to panic.
Relax, do your best, and then leave the rest to God.

 

[optimistic]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w11_qp_41.pdf
Can anyone here explain me the answer to Q7 part c? PLEASE HELP

 

[RGBM211]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w10_qp_43.pdf
http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w10_ms_43.pdf

mmm getting c as 4pie^2/GM whereas in markscheme its GM/4pie^2 explanation plz
c)i how to do :O and yea ii also

 

[leadingguy]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w11_qp_41.pdf
Can anyone here explain me the answer to Q7 part c? PLEASE HELP

the thrd wave lengh which we have calculated above in the same question is 1700 i guess. so its to high and does not lie in the spectrum frm 400 to 700nm so it wil not be absorded only the wavelenghs 654 and 488 wil be absorbed. so only two dark fringes wil be seen in the emergent waves. the spectrum will be a scatterd one due to the emergence of phototns frm the gas, as the electrons wil de-excite frm their excited state

i gues this is the ans, i have not seen the m.s yet

 

[leadingguy]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_qp_43.pdf
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_ms_43.pdf

mmm getting c as 4pie^2/GM whereas in markscheme its GM/4pie^2 explanation plz
c)i how to do :O and yea ii also

which quetion ???

 

[angelicsuccubus]

Thank you so much ... Can you please answer my final question?

http://www.xtremepapers.com/CIE/International A And AS Level/9702 - Physics/9702_s11_qp_41.pdf
- Number 6 (b)(ii)

sorry I got distracted, lets see... I haven't really studied this stuff but from what I can see it's because the current in the primary coil is not going to be in phase with the current in the secondary coil right? In Faraday's law.. rate of change of magnetic flux linkage is proportianal to the EMF and the magnetic flux becomes linkage when you multiply it with the number of turns..

the number of turns in the primary and secondary are different.. so rate of change of magnetic flux is different.. which means the Emf of the supply and the induced Emf are different.. okay.. I lost my train of thought when I read the mark scheme.. it doesn't make sense to me.. eck sorry If I confuse you further
Edit: Okay here's my simplest verison, Supply e.m.f and induced e.mf is different. E.m.f is directly proportional to rate of change of magnetic flux.. if you put it on a graph, their different rates would put them in different phases.

 

[angelicsuccubus]

I'm doing the same thing! Well I still have till tomorrow morning, so not going to panic.
Relax, do your best, and then leave the rest to God.

I haven't started the last four sections of the syllabus or the pastpapers... so it's okay + I have 2 other exams..

 

[arlery]

I haven't started the last four sections of the syllabus or the pastpapers... so it's okay + I have 2 other exams..

But you're pretty good at it so I'm guessing you don't need much work either.
I've got another paper too :S
But anyway, best of luck for all three of yours

 

[RGBM211]

which quetion ???

oooopz sorry question 1

 

[angelicsuccubus]

But you're pretty good at it so I'm guessing you don't need much work either.
I've got another paper too :S
But anyway, best of luck for all three of yours

lol what makes you say Im good at it?
but thankyou.. makes me feel a lil better.. and inshallah yours will go super well too =]
Im just scared that they'll come up with some scarey paper and I won't be able to remember anything.. considering I learnt it all in the past 20 hours or so.. sigh

 

[abdullah12]

Can someone explain to me what is line spectrum, emission spectrum and absorption spectrum? the difference?

In n11_41 Q 7)a) and Q7)c), please explain how to answer?

thanks in advance