The stopping potential necessary to reduce the phtoelectric current of zero-

Options

A. is directly proprotional to wavelength of incident light.
B. uniformly increases with the wavelength of incident light.
C. directly proportional to frequency of incident light.
D. uniformly increases with the frequnecy of incident light.

Explanation

To solve the question regarding the stopping potential necessary to reduce the photoelectric current to zero, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Photoelectric Effect**: The photoelectric effect occurs when light of sufficient frequency shines on a metal surface, causing the emission of electrons. The stopping potential (Vs) is the potential needed to stop these emitted electrons and reduce the photoelectric current to zero.

2. **Using the Photoelectric Equation**: The relationship between the stopping potential (Vs), the frequency (f) of the incident light, and the work function (Φ) of the material is given by the equation:
\[ eV_s = hf - \Phi \]
where:
- \( e \) is the charge of the electron,
- \( V_s \) is the stopping potential,
- \( h \) is Planck's constant,
- \( f \) is the frequency of the incident light,
- \( \Phi \) is the work function of the material.

3. **Rearranging the Equation**: To find the stopping potential, we can rearrange the equation:
\[ V_s = \frac{hf - \Phi}{e} \]

4. **Analyzing the Relationship**: From the equation, we can see that:
- The stopping potential \( V_s \) is directly proportional to the frequency \( f \) of the incident light. If the frequency increases, the stopping potential also increases.
- The stopping potential does not depend on the wavelength \( \lambda \) directly, but since frequency and wavelength are inversely related (\( f = \frac{c}{\lambda} \)), an increase in wavelength would correspond to a decrease in frequency, which would decrease the stopping potential.

5. **Conclusion**: Therefore, the stopping potential necessary to reduce the photoelectric current to zero is directly related to the frequency of the incident light. The correct answer is that it increases with the frequency of the light.

### Final Answer:
The stopping potential necessary to reduce the photoelectric current to zero increases with the frequency of the incident light.