Question

A Student focuses a sharp image of sun using a spherical mirror on a sheet of paper, which starts to burn after some time. Which of the following statement/statements about the mirror is/are correct?

a) It is concave spherical mirror

b) It is positive focal length

c)It is a converging mirror

• A. Both (b) and (c)
• B. Both (a) and (c)
• C. Both (a) and (b)
• D. (a), (b) and (c)

Answer 1

Answer:

B. Both (a) and (c)

A concave mirror focuses parallel light rays to a single point, making it a converging mirror and causing the paper to burn. It has a positive focal length as well. The rays from the Sun are parallel. When these rays fall on the concave mirror, they are converged to a single point on the focal plane of the mirror.