Question 350: Dual Nature of Matter and Radiation

Question

In photoelectric effect, the photo current

Accepted Answer

The photoelectric effect is a phenomenon where electrons are ejected from the surface of a material when it is exposed to light of sufficient frequency. The photo current, which is the current produced due to these ejected electrons, has specific dependencies based on the properties of the incident light.
Option A states that the photo current does not depend on the frequency of the photon but depends on the intensity of incident light. This is generally correct. The intensity of the incident light increases the number of photons hitting the surface per unit time, which in turn increases the number of electrons being ejected, and thus increases the photo current. However, the frequency of the photons determines whether electrons are ejected at all. There is a threshold frequency below which no electrons are ejected, regardless of the light intensity.
Option B states that photo current decreases with an increase in the frequency of the incident photon. This is incorrect. Increasing the frequency of the photon, provided it is above the threshold frequency, increases the energy of ejected electrons but does not decrease the photo current.
Option C states that photo current increases with an increase in the frequency of the incident photon. This is also incorrect in a general sense because the photo current is more influenced by the number of photons (intensity) rather than the energy (frequency) of individual photons. Above the threshold frequency, the photo current remains more or less constant as frequency increases.
Option D states that photo current depends on the intensity of incident radiation and its frequency. This is incorrect because the photo current specifically depends on the intensity of the incident light, provided the frequency is above the threshold frequency. The frequency mainly affects the kinetic energy of the ejected electrons, not the number of electrons ejected.
Therefore, the correct answer is:
Option A: does not depend on the frequency of photon but depends on intensity of incident light.

Answer

does not depend on the frequency of photon but depends on intensity of incident light.

Answer

decreases with Increase in frequency of incident photon.

Answer

increases with increase in frequency of incident photon.

Answer

depends with on intensity of incident radiation and its frequency.

Dual Nature of Matter and Radiation

In photoelectric effect, the photo current

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