The slope of the stopping potential versus frequency graph for photoelectric effect is equal to:

Options

A. h
B. he
C. `h//e`
D. e

Answer

To solve the question regarding the slope of the stopping potential versus frequency graph in the photoelectric effect, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Stopping Potential**:
The stopping potential (V₀) is the potential required to stop the photoelectrons emitted from a surface when illuminated by light of frequency (ν). It is related to the kinetic energy of the emitted electrons.

2. **Kinetic Energy Relation**:
The kinetic energy (KE) of the emitted electrons can be expressed as:
\[ KE = eV₀ \]
where \(e\) is the charge of the electron.

3. **Energy from Light**:
According to the photoelectric effect, the energy of the incoming photons can be expressed as:
\[ E = hν \]
where \(h\) is Planck's constant and \(ν\) is the frequency of the incident light.

4. **Photoelectric Equation**:
The energy conservation principle leads to the equation:
\[ hν = W + eV₀ \]
where \(W\) is the work function of the material.

5. **Rearranging the Equation**:
Rearranging the above equation gives:
\[ eV₀ = hν - W \]
or
\[ V₀ = \frac{h}{e}ν - \frac{W}{e} \]

6. **Identifying the Slope**:
The equation \(V₀ = \frac{h}{e}ν - \frac{W}{e}\) resembles the linear equation \(y = mx + c\), where:
- \(y\) is the stopping potential \(V₀\),
- \(x\) is the frequency \(ν\),
- \(m\) (the slope) is \(\frac{h}{e}\),
- \(c\) (the y-intercept) is \(-\frac{W}{e}\).

7. **Conclusion**:
Therefore, the slope of the stopping potential versus frequency graph is:
\[ \text{Slope} = \frac{h}{e} \]

### Final Answer:
The slope of the stopping potential versus frequency graph for the photoelectric effect is equal to \(\frac{h}{e}\).

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