Question

the focal length of a rear view mirror is 0.5m find its redius of curvature​

Answer 1

We know ,

$f = \frac{r}{2} \: \: \: \: \: \: or \: \: \: \: \: \: \: \: r \: = 2f$

Given,

Focal Length ( f ) = 0.5 m

Radius of Curvature ( R ) = ?

By Using the Formula,

R = 2f

R = 2 × 0.5

R = 1.0 m

R = 1 m

The Radius of Curvature is 1 m

If we use the 2nd Formula, i.e. f = R/2

Then we will again get the same equation ( R = 2f ) after the adjustment.

$0.5 = \frac{r}{2} \\ 0.5 \times 2 = r \: \: \: \: \: \: \: \: \: (which \: is \: 2 \times f = r) \\ 1.0 = r \\ 1m \: = r \:$

Hope Helps You !