Physics: Post your doubts here!

[A star]

not only this but nov 2012 paper is even more tough :O

 

[Jiyad Ahsan]

this paper makes me feel liike a idiot

why is it hard ? ok im going to try it.. lemme see

 

[daredevil]

2(b)(ii) seperation of atoms in the cube, V = r^3
r = (1.8x10^-23)^1/3 = 2.6x10^-8 cm

4(c)(ii) 1. Change in Ep = mg(changein h)
= 3.8 x (0.178-0.163) = - 0.057 (-ve since potential energy decreases)

2. Change in elastic P.E = 0.5k( x2^2 - x1^2)
= 0.5x180( 0.036^2 - 0.021^2)
= 0.077 J

(c)(ii) It is the speed of either one of the progressive waves travelling along oppsite directions that have superposed to form the stationary wave after the wave has been reflected at P

Hope this helps !

i didn't get 2bii
wat u did was find the radius ... how does it give us the separation between 2 atoms like if these are 2 atoms:
O--O


we need to find the dotted line part ryt? how does the radius giv us that?

 

[A star]

why is it hard ? ok im going to try it.. lemme see

a little

 

[daredevil]

guys i have a good news to all i have seen that this paper in niv timetable was easy and had alot of gaps so is hard to our paper will probably be easy

yeah i think that is y we are getting halwa papers this far bcz of the no holz in btween situation.. ooh stats is gonna make us feel like a chimp in the CAR?.... wat u said X|

 

[daredevil]

a little

"understatement of the day"

 

[Jiyad Ahsan]

i'll check out ur question but meanwhile can u tell me that in Q6 bii of the same paper why can't we use the formula v=s/t ??

umm basically you cant because since the stupid electron is accelerating velocity aint constant is it?

 

[reemkhatib]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s12_qp_61.pdf

Please help me in the first question!! it is not As i just need to know how to draw

 

[daredevil]

umm basically you cant because since the stupid electron is accelerating velocity aint constant is it?

oooh yes of course!! thankss x___x urgghhh

 

[A star]

yeah i think that is y we are getting halwa papers this far bcz of the no holz in btween situation.. ooh stats is gonna make us feel like a chimp in the CAR?.... wat u said X|

haha i was thinking the same thing xD and now p1 will be a horror to behold

 

[daredevil]

haha i was thinking the same thing xD and now p1 will be a horror to behold

yeah -__- but we'll study hard.... u know competition hai na humara?

 

[A star]

yeah -__- but we'll study hard.... u know competition hai na humara?

i dont thinknu will let me forget it till the list comes xD

 

[Jiyad Ahsan]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_22.pdf

okaays
plz explain to me
Q2b(ii) 2.
Q4cii
Q5 a(ii); b; c(ii)

of this paper and explain the answers too plzzz

2b(ii)2.
umm you found out that the volume occupied by each atom is 1.8x 10^-23
so since volume is l^3 (l here being the diameter, though volume of a sphere isnt l^3 anyways,) so length is cube-root of volume

Q4cii
p.e = m.g.(change in)h
3.8 x (0.178-0.163)
0.057 J

the other parts im still trying to get..

 

[A star]

2b(ii)2.
umm you found out that the volume occupied by each atom is 1.8x 10^-23
so since volume is l^3 (l here being the diameter, though volume of a sphere isnt l^3 anyways,) so length is cube-root of volume

Q4cii
p.e = m.g.(change in)h
3.8 x (0.178-0.163)
0.057 J

the other parts im still trying to get..

lmfao i ws seeing the wrong ms and was stupified how to use resistance to find volume xD

 

[lubna1232]

http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w12_qp_23.pdf

can someone help me with q1 e part i pleasee? the one about the resultant veloctiy

 

[Jiyad Ahsan]

lmfao i ws seeing the wrong ms and was stupified how to use resistance to find volume xD

lol omg man..

 

[daredevil]

2b(ii)2.
umm you found out that the volume occupied by each atom is 1.8x 10^-23
so since volume is l^3 (l here being the diameter, though volume of a sphere isnt l^3 anyways,) so length is cube-root of volume

Q4cii
p.e = m.g.(change in)h
3.8 x (0.178-0.163)
0.057 J

the other parts im still trying to get..

in 4eii weight is also changing y havent u considered that??? its going from being 3.8 to being 6.48 .... tabhi to extension hcange hui hai na!! :O

 

[A star]

lol omg man..

thats what i meant by making me feel an idiot

 

[Oliveme]

No, it would have been gravitational potential if I had used only mass of α nucleus. [potential = GM/R]
but since i used both the masses, it is gravitational potential ENERGY

diff btw electric potential energy n electric potential is the same
electric potential = electric potential energy / charge

Thank you very, very much gary221
I get it now.

 

[ZainH]

http://papers.xtremepapers.com/CIE/Cambridge IGCSE/Physics (0625)/0625_s12_qp_61.pdf

Please help me in the first question!! it is not As i just need to know how to draw

That's an IGCSE question, you're in the wrong board. This is for AS.