Post Your AS LEVEL PHYSICS PAPER 2 DOUBTS

[confused123]

you are doing a good job here. thanks a lot.

 

[applepie1996]

help quickyly please: How to take out terminal p.d Is there a formula for it
If the current of a wire increases, why does it short b/c its resistance should decrease right because current is increasing. And does I and R have inverse relationship and can anybody give examples as when to use it

wat do u mean by how 2 take out terminal pd????

 

[hamna0006]

thankyou

 

[applepie1996]

you are doing a good job here. thanks a lot.

ur welcum

 

[raamish]

wat do u mean by how 2 take out terminal pd????

hmmm can u explain how terminal p/d is different from actual p.d??

 

[vivo990]

but the ans is two!!

sorry instead of writing 3.39 i wrote 3.93 so the 3.50 is out of the range, thus two

 

[applepie1996]

hey, could you please help me with question 2 part d(ii) Nov 2007

power = force x velocity (this is a formula u shuld noe)
u noe the force accelerating da boy is 75N and the resistive force is -23N negative because it is acting in opposite direction so to get the total force acting on the boy u subtract 75--23=98N and speed is 4.5 m s–1 so 98 x 4.5 =440W

 

[applepie1996]

hmmm can u explain how terminal p/d is different from actual p.d??

terminal pd is the voltage from the battery
whereas the normal pd is the voltage from the appliance or circuit

 

[hamna0006]

power = force x velocity (this is a formula u shuld noe)
u noe the force accelerating da boy is 75N and the resistive force is -23N negative because it is acting in opposite direction so to get the total force acting on the boy u subtract 75--23=98N and speed is 4.5 m s–1 so 98 x 4.5 =440W

ohh ok! thanks i was confused with the signs.
Thanks a lot

 

[applepie1996]

ohh ok! thanks i was confused with the signs.
Thanks a lot

ur welcum anytym

 

[leosco1995]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w08_qp_2.pdf
Please explain Q6 (b) (i) and (ii)

 

[applepie1996]

sorry apple pie i meant 6

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

 

[applepie1996]

http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w08_qp_2.pdf
Please explain Q6 (b) (i) and (ii)

ok for diffraction of transverse waves
use a laser screen and a slit and pass the laser through the slits as the light passes through the slit it is diffracted so it spreads out onto the screen showing diffraction of transverse waves
for diffraction of longitudinal waves instead of using a screen and a laser use a c.r.o to detect the sound wave and a loudspeaker as a source of longitudinal wave

 

[leosco1995]

ok for diffraction of transverse waves
use a laser screen and a slit and pass the laser through the slits as the light passes through the slit it is diffracted so it spreads out onto the screen showing diffraction of transverse waves
for diffraction of longitudinal waves instead of using a screen and a laser use a c.r.o to detect the sound wave and a loudspeaker as a source of longitudinal wave

Hmm, okay. Thanks. ^^

BTW, one more question (it's kind of related):
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_21.pdf

Q5 (c)

 

[applepie1996]

I did. I drew an anti-node at the open end of the tube, a node at the piston end and a 2nd anti-node and node in the middle of them like this:

(open end of tube) A...N...A...N (end of tube)

..I know the first harmonic has the lowest frequency but I thought it's supposed to be 0.5 lambda.. how did you get 0.25 lambda?

there shuld only b A N A the distance between N and A is 0.4 lambda

 

[Saad (سعد)]

Hmm, okay. Thanks. ^^

BTW, one more question (it's kind of related):
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_21.pdf

Q5 (c)

Whoa... now that's one tiresome question, for a 1 hour paper.

 

[applepie1996]

Hmm, okay. Thanks. ^^

BTW, one more question (it's kind of related):
http://www.xtremepapers.com/papers/CIE/Cambridge International A and AS Level/Physics (9702)/9702_w09_qp_21.pdf

Q5 (c)

ok for diffraction
use a laser screen and a slit and pass the laser through the slits as the light passes through the slit it is diffracted so it spreads out onto the screen showing diffraction
interference
a coherent light source such as a laser beam and let it pass through two parallel slits, and the light passing through the slits is observed on a screen behind the plate. The wave nature of light causes the light waves passing through the two slits to interfere, producing bright and dark fringes on the screen
I HOPE U CAN DRAW THEM URSELF

 

[leosco1995]

ok for diffraction
use a laser screen and a slit and pass the laser through the slits as the light passes through the slit it is diffracted so it spreads out onto the screen showing diffraction
interference
a coherent light source such as a laser beam and let it pass through two parallel slits, and the light passing through the slits is observed on a screen behind the plate. The wave nature of light causes the light waves passing through the two slits to interfere, producing bright and dark fringes on the screen
I HOPE U CAN DRAW THEM URSELF

Yes, I can. Thanks.

 

[applepie1996]

Yes, I can. Thanks.

ur welcum

 

[Usama awan]

hey w11/p23 ...Q3 c(i) .....how is the striking speed 13 ,shouldn't it be 7.5 since the vertical velocity is zero?