Imagine a proton at rest a certain distance from a negatively charged plate. It is released and collides with the plate. Then imagine the similar case of an electron at rest the same distance away from a positively charged plate. In which case will the moving particle have the greater speed when the collision occurs? Why?

Solution 46E Step 1 of 3: In both cases, When proton collide with negative charged plate and when electron collide with the positive charged plate. The potential energy comes from the opposite charges attraction(will be same in both case) and after impact it will be given out as kinetic energy to the moving proton or electron. Hence in both the cases kinetic energy derived by the proton and electron will be equal. Step 2 of 3: Kinetic energy is due to the virtue of the motion of the particle and is given by, E= mv 2 2 Where E is kinetic energy of particle of mass m moving with speed v.