The correct curve between intensity of scattering (I) and the angle of diffraction `phi` in Davison - Germer experiment is :

Options

A.
B.
C.
D.

Answer

### Step-by-Step Solution:

1. **Understanding the Davison-Germer Experiment**:
- The Davison-Germer experiment demonstrated the wave nature of electrons through diffraction patterns. The intensity of scattered electrons is measured at various angles of diffraction.

2. **Identifying Key Parameters**:
- The experiment indicates that the maximum intensity of scattering occurs at a specific angle of diffraction, which is 50 degrees in this case.

3. **Analyzing the Intensity vs. Angle of Diffraction**:
- As the angle of diffraction increases from 0 degrees, the intensity of scattering will rise, reaching a peak at 50 degrees, and then it will start to decrease. This behavior is typical for diffraction patterns.

4. **Evaluating the Options**:
- The problem provides four options for the graph of intensity (I) versus angle of diffraction (φ). We need to identify which graph correctly represents the behavior described.
- **Option A**: Shows a peak at 50 degrees, which corresponds to the highest intensity.
- **Option B**: Indicates low intensity at 50 degrees, which is incorrect.
- **Option C**: Displays a straight line, which does not represent the expected curve.
- **Option D**: Does not show an increase in intensity leading up to 50 degrees, making it incorrect.

5. **Conclusion**:
- The correct graph is the one that shows the intensity peaking at 50 degrees. Therefore, **Option A** is the correct answer.

### Final Answer:
The correct curve between intensity of scattering (I) and the angle of diffraction (φ) in the Davison-Germer experiment is represented by **Option A**.

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