# For a photoelectric material, if we decrease the intensity of radiation keeping the frequency constant, then _________.

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For a photoelectric material, if we decrease the intensity of radiation keeping the frequency constant, then _________.

1. Saturation current will increase
2. Photoelectric effect will not take place
3. Maximum kinetic energy will decrease
4. Saturation current will decrease

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Correct Answer - Option 4 : Saturation current will decrease

CONCEPT:​

• Intensity is the amount of energy received per unit area. The kinetic energy of photoelectrons is directly proportional to the intensity of incident radiation, as the intensity of incident radiation increases the kinetic energy of photoelectrons increases.
• The intensity is directly proportional to the number of photoelectrons emitted.

Saturation current:​

• The maximum value of the photoelectric current is called the saturation current.
• The Saturation current implies that all the photoelectrons emitted by the emitter are immediately collected by the anode.
• The Saturation current depends on the intensity of incident radiation.

​EXPLANATION:

• As the intensity has decreased the energy received by the surface is decreased.
• As the intensity of incident radiation is decreased the number of photoelectrons emitted is decreased then the saturated current is decreased. Hence, option 4 is the answer