Two plane mirrors are inclined at an angle of `72^(@)` . The number of images of a point object placed between them will be

Options

A. 2
B. 3
C. 4
D. 5

Answer

To find the number of images formed by two plane mirrors inclined at an angle, we can use the formula:

\[ N = \frac{360^\circ}{\theta} - 1 \]

where \( N \) is the number of images and \( \theta \) is the angle between the two mirrors.

### Step-by-step Solution:

1. **Identify the angle between the mirrors**:
The angle \( \theta \) given in the problem is \( 72^\circ \).

2. **Substitute the angle into the formula**:
We will substitute \( \theta = 72^\circ \) into the formula for the number of images:
\[ N = \frac{360^\circ}{72^\circ} - 1 \]

3. **Calculate \( \frac{360^\circ}{72^\circ} \)**:
Performing the division:
\[ \frac{360}{72} = 5 \]

4. **Subtract 1 from the result**:
Now, we subtract 1 from the result obtained:
\[ N = 5 - 1 = 4 \]

5. **Conclusion**:
Therefore, the number of images formed by the two mirrors inclined at an angle of \( 72^\circ \) is \( 4 \).

### Final Answer:
The number of images formed is \( 4 \).