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A particle of mass m and charge Q moves directly towards the FIXED particle B,which haS charge Q. The speed of A is V when it is far away from B. the minimum separation between the particles is not proportional to :
a)Q RAISE TO 2
b)1/ v raise to 2
c)1/ v
d)1/m
Asked by sonali 4 months ago
Answers (1)
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The net force on A towards the right is KQ2/r2.
Therefore, vdv/dr = KQ2/mr2 = acceleration of A towards the left. (A is the red coloured particle).
So, ?vdv = (KQ2/m)?r2dr
Integrating with limits of v from initial velocity v to zero (since A comes to rest when it is at a minimum distance from B) and limits of r from infinity to d where d is the minimum distance, you can get the value of d.
That's the answer - the minimum distance of A from B.