Post Your AS LEVEL PHYSICS PAPER 2 DOUBTS

[zainabk]

And when and where do we use the 'unified mass constant' and the 'elementary charge' in radioactivity calcuations?? :|

 

[applepie1996]

Hey.Can you tell me how to solve the last part of the last question of O/N2011's 23 paper :/

6c)acceleration of alpha/acceleration of beta
a=F/m F=Eq
sooo neglect it E it eventually cancels out
so alpha acceler..... 1st:
alpha is helium nucleus so 2 proton 2 neutron
2 x 1.6 x 10 ^-19/4 x 1.67 x 10 ^-27 = 4.79 x 10^7
beta acelerat....
beta is an electron
1.6 x 10 ^-19/9.11 x 10^-31=1.76 x 10^11
so 4.79 x 10^7/1.76 x 10^11=2.7 x 10 ^-4

 

[zainabk]

Thank youu

 

[zainabk]

We are only supposed to use 'unified mass constant','elementary charge' and rest masses of electrons ,protons and neutrons from the data sheet for radioactivity questions,right??

 

[applepie1996]

Thank youu

ur welcum

 

[applepie1996]

We are only supposed to use 'unified mass constant','elementary charge' and rest masses of electrons ,protons and neutrons from the data sheet for radioactivity questions,right??

yes

 

[zainabk]

Okay thanks

 

[applepie1996]

Okay thanks

 

[Saad (سعد)]

just move it 0.25lambda to the right that is wat i think

That's what I thought too, but the mark scheme says: "horizontal line through central section of wave"; what does that mean?

The distance between adjacent nodes and adjacent antinodes is 0.5Lambda, right?

 

[leosco1995]

That's what I thought too, but the mark scheme says: "horizontal line through central section of wave"; what does that mean?

The distance between adjacent nodes and adjacent antinodes is 0.5Lambda, right?

http://www.xtremepapers.com/communi...st-your-doubts-here.9860/page-105#post-292759

 

[raamish]

What will happen to the internal energy, K.e and P.e of a substance during boiling,evaporation and etc. Can somebdy explain the concept to me?

 

[Saad (سعد)]

http://www.xtremepapers.com/communi...st-your-doubts-here.9860/page-105#post-292759

Jazak Allah Khayr!!!

 

[Soldier313]

Can someone please upload a 'CIE endorsed' AS Physics revision guide like the one we had for bio (by Mary Jones)? tx a lot!

 

[Oliveme]

can some one pls explain this ques? Question 5b (ii) why does the current have to be 40mA? I don't understand.
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s03_qp_2.pdf
http://www.xtremepapers.com/papers/...el/Physics (9702)/9702_s03_ms_1 2 3 4 5 6.pdf

 

[donorsolutions]

no it is proportional to amplitude squared

This is the general confusion here..
Intensity is directly proportional to (Amplitude)^2
as well as
(Frequency)^2

Open May 2003 Q4b(ii) 2
Now how..do you explain the decrease in the maximum brightness..simply because the intensity has decreased as wavelength has increased.
http://www.xtremepapers.com/papers/...and AS Level/Physics (9702)/9702_s03_qp_2.pdf
http://www.xtremepapers.com/papers/...el/Physics (9702)/9702_s03_ms_1 2 3 4 5 6.pdf​

 

[raamish]

http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w10_qp_35.pdf

1ai) In this part the diameter's units have to be in mm or m?
ii) HAs to be in mm2 or m2
b(iii) x should be in m or cm
c) In the table x can be given in cm or it has to be given in m?

Please help anybody

 

[applepie1996]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_qp_35.pdf

1ai) In this part the diameter's units have to be in mm or m?
ii) HAs to be in mm2 or m2
b(iii) x should be in m or cm
c) In the table x can be given in cm or it has to be given in m?

Please help anybody

alwayz give your answer in SI

 

[raamish]

alwayz give your answer in SI

ok but in the marking scheme: http://www.xtremepapers.com/papers/...nd AS Level/Physics (9702)/9702_w10_ms_35.pdf
part 1ai) is given in mm ??

 

[applepie1996]

ok but in the marking scheme: http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w10_ms_35.pdf
part 1ai) is given in mm ??

in practicals u can use any units u lyk as long as u get the end answer in the right units
lyk they ask u 2 calculate area and u use length as mm but ur area's answer is in metres so dat wuld b wrong

 

[raamish]

and for example if we have to calculate the uncertainty of the reading of a metre rule. The reading is 10. least count is 0.1 then we should take out uncertainty as: 0.1/10*100 or we should halve the least count 0.05/10*100 to take out the answer. Which 1 is it /???