Question

what is the power of lens whose focal length is 22cm?

Answer 1

Given :

Focal length  ( f ) =  + 22 cm = + 0.22 m

To find :

1 ) Power of the given lens = ?

Formula :

1) Power = 1 / f ( in metres )

Solution :

∵ P = 1 /f
∴ P = 1 / 0.22

∴ P = +4.54 D

∴The power of the given lens is + 4.54 dioptres.

Answer 2

4.54 D ans mahir Reza