What is the photoelectric effect? With the help of suitable graph show the variation of photocurrent with (i) the intensity of incident radiation. (ii) the voltage applied between cathode and anode. (iii) the frequency of incident radiation.

Explanation

### Step-by-Step Solution:

**Step 1: Define the Photoelectric Effect**
The photoelectric effect is the phenomenon in which electrons are emitted from a material (usually a metal) when it is exposed to light (or electromagnetic radiation) of sufficient frequency. When photons strike the surface of the metal, they transfer their energy to the electrons, which can then escape from the surface if the energy of the photons is greater than the work function of the metal.

**Step 2: Variation of Photocurrent with Intensity of Incident Radiation**
- **Explanation**: The photocurrent is directly proportional to the intensity of the incident radiation. As the intensity increases, more photons strike the surface of the metal, leading to the emission of more photoelectrons and thus a higher photocurrent.
- **Graph**: The graph will show photocurrent on the y-axis and intensity on the x-axis. It will be a straight line starting from the origin, indicating that as intensity increases, photocurrent increases linearly.
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