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. The corresponding stopping potential is(a) 1.8 V(b) 1.2 V(c) 0.5 V(d) 2.3 V

Answer 1

it should be the answer

Answer 2

Answer:

C) 0.5V

Explanation:

Stopping Potential or the cut-off potential is defined as the potential necessary to stop any electron from reaching on to the other side. The stopping potential Vs is related to the maximum kinetic energy of the emitted electrons.

Kmax = eVs

Kmax = eV

0.5 eV = eVs or Vs = 0.5 V

Since, the stopping potential is amount of voltage needed to stop maximum energy electron.

Here maximum Kinetic energy = 0.5 eV  (Given)

Therefore, the stopping potential = 0.5 V