A particle of mass m and positive charge q is released from point A. Its speed is found to be v when it passes through a point B. which of the two points is at higher potential ? What is the potential difference between the points?

Explanation

The points A is at higher potential than B as the particle has gained kinetic energy while moving from A to B.
The kinetic energy acquired by the particle is equal to loss in potential energy, i.e.,
`DeltaK = q( V_(A)- V_(B))` `(1)/(2) mv^(2) = q(V_(A)-V_(B))implies V_(A)-V_(B) = (1)/(2) (mv^(2))/(q)`