Question

1. Find the focal length of a mirror whose radius of curvature is 20cm ?​

Answer 1

Explanation:

Radius of curvature = 2 x focal length.

So, focal length =

2

1

× radius of curvature =

2

1

×20 cm = 10 cm

Answer 2

Answer:

Radius of curvature = 2 x focal length.

So, focal length =

1/2 × radius of curvature

=1/2×20cm = 10 cm