Physics 2003 JAMB Past Questions - Question 44: The maximum kinetic energy of the photoelectrons emitted from a metal surface is 0.34eV. If the work function of the metal surface is 1.83eV, find the stopping potential.

Correct Answer

B

Explanation

The stopping potential (V) for photoelectrons can be calculated using the following equation:

V = Energy of incident photons - Work function

In this case, the energy of incident photons is equal to the maximum kinetic energy of the photoelectrons. Given that the maximum kinetic energy (K.E) is 0.34 eV and the work function (φ) is 1.83 eV, you can calculate the stopping potential (V) as follows:

V = K.E - φ
V = 0.34 eV - 1.83 eV

V = -1.49 eV

So, the stopping potential is -1.49 eV. Note that the negative sign indicates that the photoelectrons are being slowed down or "stopped" as they move through an electric potential difference.