The angle of incidence on a plane mirror is `30^@` . The angle between the incident ray and the reflected ray is

Options

A. `30^@`
B. `15^@`
C. `60^@`
D. `90^@`

Answer

To solve the problem, we need to find the angle between the incident ray and the reflected ray when the angle of incidence on a plane mirror is given as \(30^\circ\).

### Step-by-Step Solution:

1. **Understand the Setup**:
- We have a plane mirror, and the normal (a line perpendicular to the surface of the mirror) is drawn at the point where the incident ray strikes the mirror.

2. **Identify the Angle of Incidence**:
- The angle of incidence (\(i\)) is given as \(30^\circ\). This is the angle between the incident ray and the normal.

3. **Apply the Law of Reflection**:
- According to the law of reflection, the angle of incidence is equal to the angle of reflection (\(r\)). Therefore, if the angle of incidence is \(30^\circ\), the angle of reflection is also \(30^\circ\).

4. **Determine the Angles with Respect to the Normal**:
- The incident ray makes an angle of \(30^\circ\) with the normal.
- The reflected ray also makes an angle of \(30^\circ\) with the normal.

5. **Calculate the Angle Between the Incident Ray and the Reflected Ray**:
- The angle between the incident ray and the reflected ray can be found by adding the angle of incidence and the angle of reflection:
\[ \text{Angle between incident ray and reflected ray} = \text{Angle of incidence} + \text{Angle of reflection} = 30^\circ + 30^\circ = 60^\circ \]

6. **Final Answer**:
- The angle between the incident ray and the reflected ray is \(60^\circ\).

### Summary:
The angle between the incident ray and the reflected ray is \(60^\circ\).