Question

A concave mirror of focal length 15 cm forms an image at a distance 45cm from the mirror.how far is the object placed in front of the mirror? .draw a ray diagram.

Answer 1

Answer:

the object is placed 22.5 cm from the mirror.

Explanation:

1/v +1/u = 1/f

hence, 1/u = 1/15 + 1/45

1/u = (3-1)/45

1/u = 2/45

or u = 45/2

u = 22.5