Question

A certain concave mirror is found to form an image of the Sun at a distance of 8 m from the mirror. What is the radius of curvature of this mirror?

8 m
12 m
16 m
24 m

Answer 1

Answer on Question#52732 - Physics - Optics

A certain concave mirror is found to form an image of the Sun at a distance of $8\mathrm{m}$ from the mirror. What is the radius of curvature of this mirror?

$8\mathrm{m}$

$12\mathrm{m}$

$16\mathrm{m}$

$24\mathrm{m}$

**Solution:**

Since the Sun is located at very large distance, its image is formed at the focal plane. Therefore, the focal length of the given mirror is

$$f = 8 \mathrm{m}$$

It is known that the radius of curvature of the concave mirror is twice the focal length:

$$R = 2f = 16 \mathrm{m}$$

**Answer:** 16 m.