Author Topic: ALL CIE PHYSICS DOUBTS HERE !!!  (Read 152726 times)

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #975 on: March 18, 2012, 08:12:24 pm »
a)cos it is easier to breathe in.
see attachment

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #976 on: March 18, 2012, 08:26:53 pm »
a)gamma rays
b)see attachment

Offline ashwinkandel

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #977 on: March 24, 2012, 08:00:52 am »
Questions from Oscillation
I have attached four questions below.

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #978 on: March 24, 2012, 08:26:09 am »
I will make some videos tomorrow for these

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #979 on: March 25, 2012, 08:32:28 am »
Here are your answers.
Will also make some videos

Offline ashwinkandel

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #980 on: March 26, 2012, 02:05:22 pm »
Sir(astarmathsandphysics), I think you forgot the answer to fourth question.

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #981 on: March 26, 2012, 02:14:28 pm »
You are right sorry.

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #982 on: March 26, 2012, 02:34:46 pm »
a)natural resonance frequency of system shown be nowhere near frequency of earthquake waves.
b)gradient is negative and constant so a=-kx
c)k=omega^2=10/0.02=500 so omega=sqrt(500)=22.4
f=omega/2pi=22.4/6.28=3.6 Hz

Offline silvercameron

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #983 on: April 02, 2012, 01:27:55 pm »
can someone pls explain why the answer to Q.no. 11 is A? See attachment.

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #984 on: April 02, 2012, 09:11:17 pm »
Use Newtons Law of restitution
e=(separation speed)/(approach speed)=(v2-v1)/(u1+u2)
e=1 for a perfectly elastic collision so v2-v1=u1+u2
answer is D

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #985 on: April 02, 2012, 09:14:47 pm »
Q10
Use Newtons Law of restitution
e=(separation speed)/(approach speed)=(v2-v1)/(u1+u2)
e=1 for a perfectly elastic collision so v2-v1=u1+u2
answer is D
q11
Applying F=ma for 2 kg mass 2g-T=2a
applying F=ma for 8kg mass T-6=8a
add these to get 2g-6=10a so a=(2g-6)/10=1.36

Offline Physics09

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Urgent help!!
« Reply #986 on: April 03, 2012, 12:11:42 pm »
« Last Edit: April 03, 2012, 12:36:33 pm by Physics09 »

Offline astarmathsandphysics

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #987 on: April 03, 2012, 11:33:42 pm »
see attachment

Offline Physics09

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #988 on: April 04, 2012, 10:01:48 am »

Offline SkyPilotage

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Re: ALL CIE PHYSICS DOUBTS HERE !!!
« Reply #989 on: April 04, 2012, 03:01:23 pm »
Q27 - Electric Field direction is always from +ve to -ve plate. SO if the electric field direction is away from you means the +ve plate is closer to you than the -ve plate, therefore the electron beam goes towards the +ve plate which is towards you so the answer is D!

Q34 - Total Resistance is 1.5R ---> so I^2 = P / 1.5R = 8 A^2 ---> I = 2.83 A
Here I took the value of R as 1 ohm, you can take it as any value you want as long as you are cosistent with all the resistors P,Q and R.
So P across P = (2.83)^2 x 1 = 8 Watts
P across Q = (2.83 / 2 ) ^2 x 1 = 2 Watts
P across R = P across R2 = 2 Watts.
Answer is A

There you have it!
« Last Edit: April 04, 2012, 03:03:16 pm by SkyPilotage »