Question

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

Answer 1

We know that Radius of Curvature is always double of the focal length and the focal length is half the radius of curvature.

R = 2 × F

R = Radius of Curvature

F = Focal Length

In the Given Question, we have :-

The Radius of curvature is 20cm

R = 2F

=> F = R/2

=> F = 20/2

=> F = 10cm

Hence we calculated the Focal Length as 10cm.

MORE FORMULAE FOR SPHERICAL MIRROR :-

1/f = 1/u + 1/v

u = distance of object

v = distance of image

Answer 2

Answer:

10cm

Explanation:

Given;

curvature of a spherical mirror =20cm.

To find = Focal length

Sol:

By using the formula

R= 2×F

=> R = 2F

=> F = R/2

=> F = 20/2 (Given)

=> F = 10 cm