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JEE Main201912 Jan 2019Morning ShiftPhysicsElectrostaticsActual

There is a uniform spherically symmetric surface charge density at a distance R 0 from the origin. The charge distribution is initially at rest and starts expanding because of mutual repulsion. The figure that represents best the speed V R t of the distribution as a function of its instantaneous radius R t is:

Correct answer

0

Step-by-step solution

U i + K i = U f + K f K Q 2 2 r 0 + 0 = K Q 2 2 r + 1 2 m v 2 v 2 = K Q 2 m 1 r 0 - 1 r v = K Q 2 m 1 r 0 - 1 r

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