Question

A pair of glasses on your face produces images that are 4 cm from the lens if the objects are 100 cm away what is the focal length of that lens ?

Answer 1

Focal Length of the lens is 3.846 cm.

Step-by-step explanation:

Image Distance ( i ) = 4 cm

Object Distance ( o ) = 100 cm

Find,

Focal length =?

Focal length of pair of glasses can be calculated as -

`1/f = 1/o + 1/i` ............. ( here 1 / o it's o = object distance )

`1/f = 1/100 + 1/4\\\\1/f = 0.26\\\\f = 3.846 cm`

Focal Length of the lens is 3.846 cm.