An electron , with charge of `-1.60 xx 10^(19) C`, accelerates from rest through a potential difference V. A proton , with a charge of `+ 1.60 xx 10^(-19) C `, accelerates from rest through a potential difference `-V` . Is the final speed of the electron (a) more than , (b) less than , or (c ) same as the final speed of the proton ?

Explanation

The electron and proton have charges of equal magnitude therefore they have equal changes in electric potential energy. As a result their final kinetic energies are equal . Since the election has less mass than the proton however its speed must be greater .