Question

The focal length f is related to the radius of curvature r of the spherical convex mirror by ______.

Options

• `f = +1/2 r` 

• f = −r

• `f = -1/2 r` 

• f = r

Answer 1

The focal length f is related to the radius of curvature r of the spherical convex mirror by `bbunderline(f = +1/2 r)`.

Explanation:

For a convex mirror, the focus is behind the mirror.

So, its focal length (f) is positive.

∴ `f = +1/2 r`