Question

A man holds a spherical shaving mirror of radius of curvature 60 cm, and focal length 30 cm, a t a distance of 15 cm, from his nose. Find the position of image, and calculate the magnification.

Answer 1

Radius of curvature R= -60 cm (concave mirror)
f = -30 cm
u= -15 cm
We have
1/v+1/u=1/f
1/v+1/-15=1/-30
1/v=1/15+1/-30
1/v=1/30
v=30 cm
m=-v/u
m=-30/-15
m=2
so the image is formed 30 cm behind the mirror and the magnification is +2