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ALL CIE PHYSICS DOUBTS HERE !!!

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TJ-56:

--- Quote from: $!$RatJumper$!$ on November 10, 2010, 05:15:05 pm ---Haha looks like the same question is getting to all of us :P I also need help on that :P

--- End quote ---
5(a)
1. The waves should meet in antiphase at M. ( phase difference = pie)
2. Sources must emit waves having same amplitude.

(b)
So the wavelength ranges from 330/4000  to 330/1000 (v/f) which is 8.25 to 33 cm
The distance from S2 to M is 128 (root(100sqr +80sqr))
So the phase difference is 128-100 which is 28
using the equation
phi/2pi = AB/lambda
as phi must be pi rad, 1/2 = AB/lambda
AB= 28
so making lambda the subject: lambda= (28*2)/n , where n could be 1,3,5,7 (to be out of phase)
so trying out 1,3,5,7 give us 56, 18.7, 11.2, and 8 respectively, as 18.7 and 11.2 are the only 2 values inside the range i calculated at the beginning, then the number is 2
hope that was helpful

TJ-56:

--- Quote from: Deadly_king on November 10, 2010, 04:56:54 pm ---7.(b)(ii)

1. 1.1 MeV is supplied in the form of kinetic energy of the alpha-particle.

2. First you should convert 1.1 MeV into joules. => K.E = (1.1 x 106) x (1.6 x 10-19) = 1.76 x 10-13 J

Now you equate K.E = 0.5mv2 = 1.76 x 10-13

Mass of an alpha-particle is 4u = 4(1.67 x 10-27)kg

Hence speed of alpha-particle is found to be the square root of 2(1.76 x 10-13)/4(1.67 x 10-27)

v = 7.3 x 106 ms-1

Hope it helps :)

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Thanx for the answer +rep
But can u explain further part 1 of the question
thanx in advance

thecandydoll:
O/N 2002 Q3 C :(

ashish:

--- Quote from: thecandydoll on November 11, 2010, 02:47:35 am ---O/N 2002 Q3 C :(

--- End quote ---

according to me the time in contact is 0.15 ( from the graph)
 F= change in momentum/time
= 0.35/0.15
=2.33N

$!$RatJumper$!$:

--- Quote from: TJ-56 on November 10, 2010, 09:56:29 pm ---5 (b)

So the wavelength ranges from 330/4000  to 330/1000 (v/f) which is 8.25 to 33 cm
The distance from S2 to M is 128 (root(100sqr +80sqr))
So the phase difference is 128-100 which is 28
using the equation
phi/2pi = AB/lambda
as phi must be pi rad, 1/2 = AB/lambda
AB= 28
so making lambda the subject: lambda= (28*2)/n , where n could be 1,3,5,7 (to be out of phase)
so trying out 1,3,5,7 give us 56, 18.7, 11.2, and 8 respectively, as 18.7 and 11.2 are the only 2 values inside the range i calculated at the beginning, then the number is 2
hope that was helpful


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What is this equation?? I've never heard about it. What is it used to calculate and when should we use it?

By the way, whats phi?

phi/2pi = AB/lambda

Thankx

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