A positive charge Q is uniformly distributed throughout the volume of dielectric sphere of radius R.A point mass having charge +q and mass m is fired towards the center of the sphere with velocity v from a point distance r(r>R) from the center of the sphere .Find the minimum velocity v so that it can penetrate R/2 distance of the sphere. Neglect any resistance other than electric interaction. Charge on the small mass remains constant throughout the motion.

Prakhar Shukla , 8 Years ago

Grade 12