Question

What will be the focal length of a concave mirror if its radius of curvature is 10.5 CM?​

Answer 1

Explanation:

if radius of curvature is 10.5 cm, we know f=R/2

focal length=10.5/2=5.25 cm.

Answer 2

$\underline{\underline \bold{ \large{ \: \: Answer : \: \: }}}$

$\to$ Focal length ( F ) = 54.5 cm

$\underline{\underline \bold{ \large{ \: Explanation : \: \: \: }}}$

$\to$ Radius of curvature ( R ) = 10.5 cm

$\to$ Let , Focal length ( F )

$\large \fbox{{\fbox{ \bold{ F = \frac{ \: R \: }{2} }}}}$

$\to F = \frac{10.5}{2} \\ \\ \to F = \frac{105}{2} \\ \\ \to F = 54.5 \: \: \bold{ cm}$