A ray is incident at an angle `40^@` with a mirror. The angle between the normal and reflected ray is

Options

A. `40^@`
B. `50^@`
C. `60^@`
D. `80^@`

Answer

To solve the problem, we need to determine the angle between the normal and the reflected ray when a ray of light is incident at an angle of \(40^\circ\) with a mirror.

### Step-by-Step Solution:

1. **Identify the Given Information**:
- The angle of incidence (\(I\)) is given as \(40^\circ\).

2. **Understand the Law of Reflection**:
- According to the law of reflection, the angle of incidence is equal to the angle of reflection. This can be expressed as:
\[ I = R \]
where \(I\) is the angle of incidence and \(R\) is the angle of reflection.

3. **Determine the Angle with the Normal**:
- The angle of incidence is measured between the incident ray and the normal to the mirror. Since the angle of incidence is \(40^\circ\), we can find the angle between the normal and the reflected ray using the following relationship:
\[ \text{Angle between normal and reflected ray} = R \]

4. **Calculate the Angle of Reflection**:
- Since \(I = R\), we have:
\[ R = 40^\circ \]
Therefore, the angle between the normal and the reflected ray is also \(40^\circ\).

5. **Final Answer**:
- The angle between the normal and the reflected ray is \(40^\circ\).

### Summary:
The angle between the normal and the reflected ray is \(40^\circ\).