The middle point of the mirror is called

Options

A. pole
B. centre of sphere
C. centre of curvature
D. none of these

Answer

**Step-by-Step Solution:**

1. **Understanding the Mirror Structure**: Mirrors can be classified into two main types: concave mirrors and convex mirrors. Both types are sections of a sphere.

2. **Identifying the Middle Point**: The middle point of a mirror is a specific location that plays a crucial role in its optical properties.

3. **Defining the Pole**: The middle point of the mirror is called the "pole." It is the point on the mirror's surface that is equidistant from the edges of the mirror.

4. **Understanding Related Terms**:
- The line that connects the pole to the center of curvature (the center of the sphere from which the mirror is made) is known as the "principal axis."
- The center of curvature is the center of the sphere from which the mirror is derived.

5. **Conclusion**: Therefore, the answer to the question is that the middle point of the mirror is called the "pole."

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