AP EAMCET Engineering 22 Apr 2019 Shift 1 Paper

A ball of mass lg having a charge of 20 ∩C is tied to one end of a string of length 0.9 m can rotate in a vertical plane in a uniform electric field 100 NC−1 directed upwards. The minimum horizontal velocity that must be given to the ball at the lowest position so that it completes the vertical circle is (g = 10 ms−2)