In the davisson- German experiment, if the scattering angle is 60°, then glancing angle is equal to

Options

A. 30°
B. 45°
C. 60°
D. 90°

Answer

To solve the problem regarding the Davisson-Germer experiment, we need to find the glancing angle when the scattering angle is given as 60°.

### Step-by-Step Solution:

1. **Understanding the Angles**: In the Davisson-Germer experiment, we have three angles to consider:
- The scattering angle (θ), which is given as 60°.
- The glancing angles (φ), which are equal on both sides of the scattering angle.

2. **Setting Up the Equation**: The sum of the angles in this scenario can be expressed as:
\[ 2\phi + \theta = 180° \]
where θ is the scattering angle and φ is the glancing angle.

3. **Substituting the Given Value**: We know that θ = 60°. Substituting this into the equation gives:
\[ 2\phi + 60° = 180° \]

4. **Solving for φ**: To isolate φ, we first subtract 60° from both sides:
\[ 2\phi = 180° - 60° \]
\[ 2\phi = 120° \]

5. **Dividing by 2**: Now, we divide both sides by 2 to find φ:
\[ \phi = \frac{120°}{2} = 60° \]

6. **Conclusion**: Therefore, the glancing angle (φ) is equal to 60°.

### Final Answer:
The glancing angle is 60°.

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