Question

Photoelectric emission is possible at all frequencies.

(a) True

(b) False

The question was asked in quiz.

The doubt is from Photoelectric Effect topic in portion Dual Nature of Radiation and Matter of Physics – Class 12

Answer 1

The correct answer is (b) False.

Explanation:

Photoelectric emission is not possible at all frequencies. According to the photoelectric effect, electrons are emitted from a metal surface when it is exposed to light (or photons) of a certain frequency. However, for photoelectric emission to occur, the frequency of the incident light must be above a certain threshold frequency. This frequency corresponds to the work function of the metal, which is the minimum energy required to eject an electron from the metal's surface.

If the frequency of the incident light is below this threshold, no photoelectric emission will occur, regardless of the intensity of the light. This was a key finding of Albert Einstein’s work on the photoelectric effect, which contributed significantly to the development of quantum theory.

Thus, photoelectric emission is only possible at frequencies above the threshold frequency for the specific material in question.