If a virtual image is formed along the principal axis 12 cm from a concave mirror with the focal length 23 cm,what is the object distance from the mirror?
A)11.0 cm
B)25 cm
C)13 cm
D)7.9 cm
E)4.0 cm

Question

Quizplus · Accepted Answer

Using the mirror equation (1/f = 1/do + 1/di), where f is the focal length (-23 cm for concave mirror) and di is the image distance (-12 cm for virtual image), solving for do gives approximately 7.9 cm.

If a Virtual Image Is Formed Along the Principal Axis