Physics: Post your doubts here!

[sma786]

Hey,
Does anybody want to do past papers with me? <3
AS past papers I mean
Inbox me!
xx

 

[Musab100]

A2 physics topical questions !!!!

 

[GlitteringLights]

hi i have a tiny doubt it the latest p2 paper
ques #2 part (a)
why have they done 0.8 x 10^-6 instead of 0.8 x 10^-3? ( aren't we supposed to convert from cm to m? or am i missing something )

 

[1357911]

hi i have a tiny doubt it the latest p2 paper
ques #2 part (a)
why have they done 0.8 x 10^-6 instead of 0.8 x 10^-3? ( aren't we supposed to convert from cm to m? or am i missing something )

to convert microfarad to meters.

 

[GlitteringLights]

to convert microfarad to meters.

isn't microfarad for capacitance? i hope u mean microsecond xD ok so u dont convert the 4 cm from the graph to m, u convert the time?

 

[1357911]

isn't microfarad for capacitance? i hope u mean microsecond xD ok so u dont convert the 4 cm from the graph to m, u convert the time?

oh. I dint look at the unit after micro. yeah its micro sec/// . Yeah u convert the time.

 

[GlitteringLights]

oh. I dint look at the unit after micro. yeah its micro sec/// . Yeah u convert the time.

haha kay thanks

 

[1357911]

http://papers.xtremepapers.com/CIE/...and AS Level/Physics (9702)/9702_s08_qp_4.pdf
Can anyone explain Q12 part b please?

 

[danial 234]

can any1 help me with mcq 21
http://papers.xtremepapers.com/CIE/...nd AS Level/Physics (9702)/9702_w12_qp_13.pdf

 

[Iridescent]

What happens to the diffraction pattern if light does not strike normally to the grating?
Hassan Ali Abid

 

[danial 234]

hi i have a tiny doubt it the latest p2 paper
ques #2 part (a)
why have they done 0.8 x 10^-6 instead of 0.8 x 10^-3? ( aren't we supposed to convert from cm to m? or am i missing something )

the time taken by the pulse to travel whole distance is o.8 micro sec... or o.8 x 10^-6...
time taken to reach the reflector is o.4 micro sec
so d=3x10^8 x 0.4x10^-6 = 240 m ...
we wont convert cm into m ... cz the calibration and the time... both use cm... and cm will be cancelled while calculating time
1 cm= 0.2 micro sec
4 cm= 0.8 micro sec

 

[sara kamal]

http://papers.xtremepapers.com/CIE/Cambridge International A and AS Level/Physics (9702)/9702_s08_qp_4.pdf
Can anyone explain Q12 part b please?

formulas u will have to use..
attenuation=10 x log(P in/P out)
signal to noise ratio=10 x log (P out/P noise)
attenuation per uni length=total att/total lenth

do as follow
1 find power out......using secong formula.. 30=10 x log(p out/6.5x10-6) so p out=6.5x10-3W
2.find attenuation using formula 1 att=1o x log(26x10-3/6.5x10-3) so attenuation=6.02dB
3 finally find length using formula 3 length= 6.02/0.2=30 km

 

[goodluckayesha]

formulas u will have to use..
attenuation=10 x log(P in/P out)
signal to noise ratio=10 x log (P out/P noise)
attenuation per uni length=total att/total lenth

do as follow
1 find power out......using secong formula.. 30=10 x log(p out/6.5x10-6) so p out=6.5x10-3W
2.find attenuation using formula 1 att=1o x log(26x10-3/6.5x10-3) so attenuation=6.02dB
3 finally find length using formula 3 length= 6.02/0.2=30 km

for the 1st step the formula ok is understood then u make pout the subject then wht has to be done i dont get then how to get it plz elaborately explain the first step

 

[sma786]

A2 physics topical questions !!!!

I love you

 

[sma786]

Is there any way I can pass physics A levels without studying?

 

[1357911]

I love you

Excuse Me. In your limits please.

 

[sma786]

Excuse Me. In your limits please.

Was I speaking to you?
I dont think so
Oh and those words are within my limits

 

[1357911]

Was I speaking to you?
I dont think so
Oh and those words are within my limits

No you werent. But people dont speak like this here.
U werent. It may be a joke for you. But people dislike it here. So please.

 

[sma786]

No you werent. But people dont speak like this here.
U werent. It may be a joke for you. But people dislike it here. So please.

Didn't know there were 'speaking rules' here,
And really, I'd think people in this thread would be more mature.

 

[1357911]

Didn't know there were 'speaking rules' here,
And really, I'd think people in this thread would have grown up with less sensitivity.

Oh please. Thers something called manners Miss sma786. And people are surely grown up here with quiet a lot og good manners. They have some respect. Some self respect. Try to speak with respect with the opposite gender.