Radius of curvature of a concave mirror is always ........ to the mirror.

Options

A. parallel
B. perpendicular
C. inclined at `60^@`
D. inclined at `45^@`

Explanation

To determine the relationship between the radius of curvature of a concave mirror and the mirror itself, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of Radius of Curvature**:
The radius of curvature is defined as the radius of the sphere from which the mirror is a part. For a concave mirror, this radius is directed towards the center of the sphere.

2. **Identify the Orientation of the Mirror**:
A concave mirror is curved inward, resembling a portion of a sphere that is hollowed out.

3. **Visualize the Geometry**:
When you visualize a concave mirror, the center of curvature lies along the axis of the mirror, extending outward from the surface of the mirror.

4. **Determine the Relationship**:
The radius of curvature, being a straight line from the center of curvature to the mirror's surface, will always be directed perpendicularly to the surface of the mirror at the point where it meets the mirror.

5. **Conclude the Answer**:
Therefore, the radius of curvature of a concave mirror is always **perpendicular** to the mirror.

### Final Answer:
The radius of curvature of a concave mirror is always **perpendicular** to the mirror.

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