Question

chp 22 q14

A shaving/makeup mirror is designed to magnify your face by a factor of 1.40 when your face is placed 24.5 cm in front of it.

Part A

What type of mirror is it?

Part B

Describe the type of image that it makes of your face.

Part C

Calculate the required radius of curvature for the mirror.

Answer 1

magnification = m = 1.4

object distance = p = 24.5 cm

a) image is magnified so it is concave mirror

b) image is magnified, up right, virtual

c) m = - q / p

      1.4 = - q / 24.5

      q = - 34.3 cm

      1/f = 1/p + 1/q

        1/f = 1/24.5 - 1/34.3

            f = 85.75 cm

radius of curvature = R = 2f = 2* 85.75 = 171.5 = 172 cm