The radius of curvature of a convex mirror is 40 cm. find it's focal length.
Focal length = 12\dfrac{1}{2}21 x Radius of curvature
Given,
R = 40 cm
Substituting the values in the formula above we get,
Focal length=12×40Focal length=20 cm\text{Focal length} = \dfrac{1}{2} \times 40 \\[0.5em] \text{Focal length} = 20 \text{ cm}Focal length=21×40Focal length=20 cm
Hence, focal length of the convex mirror = 20 cm.
