The radius of curvature of a spherical mirror is 20 cm. What is its focal length?

20 cm

No worries! We‘ve got your back. Try BYJU‘S free classes today!

10 cm

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

30 cm

No worries! We‘ve got your back. Try BYJU‘S free classes today!

40 cm

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is B
10 cm

Radius of curvature, R = 20 cm
Radius of curvature of a spherical mirror = 2 $\times$ Focal length (f)
R = 2f
$f = \frac{R}{2} = \frac{20}{2} = 10$
Hence, the focal length of the given spherical mirror is 10 cm.

Suggest Corrections

243

Similar questions

If AB = 10 cm & DB = 40 cm (diameter). What is the radius of curvature & focal length?

If focal length of a spherical mirror is 20 cm, then its radius of curvature is equal to