A particle having mass m and charge q is projected with a speed u against a uniform electric field E . Determine the distance it will cover before coming to momentary rest.

Step-by-step solution

The force acting on the particle due to the uniform electric field is F = qE . The retardation of the particle is a = F m = qE m . Using the third equation of kinematics, v^2 = u^2 - 2as . Since the particle comes to momentary rest, its final velocity v = 0 . Substituting the values, 0 = u^2 - 2 ( qE m ) s . Solving for the distance s , we get s = mu^2 2qE .