Question

In photoelectric emission process from a metal of work function 1.8 eV the kinetic energy of most energetic electrons is 0.5 eV.

Answer 1

The calculation will be framed thus:

The answer is B. 0.5 V. The reason is that stopping potential= maximum Kinetic energy

eV= KE max

stopping potential= maximum Kinetic energy

eV=KE maximum

stopping potential is usually the speed required to stop a moving electron that has the maximum amount of kinetic energy. This actually stops the electron from reaching out to the other side of the plate.