Question

For a perfectly black body, the graph is plotted between the frequency of the radiation with maximum intensity (v_m) and the absolute temperature T. Out of the following, which is the correct graph?

 

Options

• D

• B

• C

• A

Answer 1

B

Explanation:

The stopping potential is the voltage required to prevent any electron from reaching the outside world. When the radiation frequency exceeds these threshold frequencies, electrons are released from the metal surface.

So, at threshold frequency (v₀), electrons are withdrawn, and more energy is required to stop these electrons, i.e. the stopping potential grows as frequency increases beyond v₀ because more electrons are expelled from the metal surface. As a result, the correct graph is B.