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A positive charge Q is uniformly distrib...

A positive charge Q is uniformly distribut along a circular ring of radius R. A small tc charge q is placed at the centre of the ring per figure, Then

A

If q gt 0 and is displaced away from th centre in the plane of the ring, it will b pushed back towards the centre.

B

If q lt 0 and is displaced away from the centr in the plane of the ring, it will never return ti the centre and will continue moving till I hits the ring.

C

If q lt 0, it will perform SHM for smai displacement along the axis.

D

q at the centre of the ring is in an unstabh equilibrium within the plane of the ring fo q gt 0

Text Solution

Verified by Experts

The correct Answer is:
A, B, C
Positive charge Q is distributed uniformly ove the outer surface of sphere, hence E inside it i, zero.
Hence, no effect on Q by q.
Two cases are possible due to attraction ano repulsion between Q and q. Case 1 : If q is positive then repulsion will be there between Q and q.
This will push q towards centre. Case 2 : If q is negative, then attraction will be there between Q and q. This will pull q towards surface and hence it will not turn back to centre.
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