Question

6. The radius of curvature of a concave mirror
is 40 cm. Its focal length is
a) 20 cm
b) 40 cm
c) 60 cm
d) 80 cm​

Answer 1

Answer:

Explanation:

The distance from the pole to the center of curvature is called the radius of curvature(r). The distance from the pole to the focal point is called the focal length (f). The focal length of a spherical mirror is approximately half its radius of curvature.

 A]So, focal length(f) = (radius of curvature(r))/2

f = 40/2 cms

f = 20 cm

Answer 2

A) 20 cm is the correct answer.