A photocell employs photoelectric effect to convert

Options

A. change in the frequency of light into a change in electric voltage
B. change in the intensity of illumination into a change in photoelectric current.
C. change in the intensity of illumination into a change in the work function of the photocathode
D. change in the frequency of light into a change into the electric current

Answer

To solve the question regarding what a photocell employs the photoelectric effect to convert, we can break down the process step by step.

### Step-by-Step Solution:

1. **Understanding the Photoelectric Effect**: The photoelectric effect is a phenomenon where electrons are emitted from a material (usually a metal) when it is exposed to light of sufficient frequency. This means that light can provide enough energy to knock electrons out of the material.

2. **Components of a Photocell**: A photocell consists of a cathode and an anode. When light (photons) strikes the cathode, it causes the emission of electrons from the cathode surface.

3. **Emission of Electrons**: The emitted electrons are then accelerated towards the anode due to the electric field present between the cathode and anode. This movement of electrons constitutes an electric current.

4. **Current Generation**: The current generated in the photocell is known as photoelectric current. This current is directly related to the intensity of the light illuminating the photocell.

5. **Intensity and Frequency**: While the frequency of the light must be above a certain threshold for the photoelectric effect to occur, the intensity of the light (which is the amount of energy per unit area) can vary. An increase in intensity leads to an increase in the number of emitted electrons, thus increasing the photoelectric current.

6. **Conclusion**: Therefore, a photocell employs the photoelectric effect to convert changes in the intensity of illumination into changes in photoelectric current.

### Final Answer:
A photocell employs the photoelectric effect to convert changes in the intensity of illumination into changes in photoelectric current.

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