Question

Which of the following options represent the variation of photoelectric current with the property of light shown on the x-axis? 

• A. A and C
• B. A and D
• C. B and D
• D. A only

Hint:

Remember the key laws of the photoelectric effect: 1. Photoelectric emission occurs only if the frequency of incident light is above a certain threshold frequency. 2. The photoelectric current is directly proportional to the intensity of incident light (for a frequency above the threshold). 3. The kinetic energy of the emitted photoelectrons depends on the frequency of incident light and is independent of the intensity.

Answer 1

The Correct Option is D

The problem involves understanding how photoelectric current varies with different properties of light. In the context of the photoelectric effect, the photoelectric current depends primarily on two factors: the intensity of the light and the frequency of the light.

• Intensity of Light: The photoelectric current is directly proportional to the intensity of the incident light. Higher intensity means more photons striking the surface, which results in more electrons being emitted and hence, a higher current, assuming the frequency is above the threshold frequency.
• Frequency of Light: The frequency must be above the material's threshold frequency for electrons to be emitted. However, once above the threshold, a change in frequency doesn't affect the current, but it affects the kinetic energy of the emitted electrons.

Based on these principles, the option 'A only' is correct if it indicates the variation of photoelectric current with the intensity of light while holding the frequency constant above the threshold. Therefore, the correct option is A only.