A prism produces a minimum deviation § in a light beam. If three such prisms are combined, the minimum deviation produced will be

Options

A. 45
B. 25
C. 5
D. 0

Answer

To solve the problem of finding the minimum deviation produced when three identical prisms are combined, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Minimum Deviation**:
- A prism causes a deviation in the path of light. The minimum deviation (denoted as δ) occurs when the light ray passes through the prism symmetrically, meaning it enters and exits the prism at equal angles relative to the base of the prism.

2. **Single Prism Deviation**:
- For a single prism, the minimum deviation is given as δ. This is the angle by which the light beam is deviated from its original path when passing through the prism.

3. **Combining Three Prisms**:
- When three identical prisms are placed in succession, the light passing through the first prism will experience a deviation of δ.
- As the light exits the first prism, it enters the second prism. The second prism will also cause a deviation of δ.
- Finally, the light exits the second prism and enters the third prism, where it will again experience a deviation of δ.

4. **Calculating Total Deviation**:
- The total deviation when light passes through all three prisms can be calculated as follows:
- Deviation from the first prism: +δ
- Deviation from the second prism: +δ
- Deviation from the third prism: +δ
- Therefore, the total deviation (Δ) is:
\[ \Delta = \delta + \delta + \delta = 3\delta \]

5. **Conclusion**:
- The minimum deviation produced when three identical prisms are combined is 3δ.

### Final Answer:
The minimum deviation produced when three such prisms are combined will be **3δ**.