Question

The magnification of a concave mirror is 1 . Find the object distance , if the focal length is 15 cm.

Answer 1

Answer:

The distance of the object, u = 30 cm

Explanation:

Given,

Magnification, m = 1

Focal length, f = 15 cm

We know,

m = v/u

or, 1 = v/u

or, v = u

We know,

1/u + 1/v = 1/f

or, 1/u + 1/u = 1/15

or, 2/u = 1/15

or, u = 30