Question

An object placed 30 cm from a concave lens forms a virtual erect image at a distance of 10 cm from the lens. The magnification produced by the lens is?

• A. -1/3
• B. -3
• C. 1/3
• D. 3

Answer 1

Answer:

A. -1/3

• Magnification (m) = -v/u where v is the image distance and u is the object distance.

• Given: u = -30 cm (object distance is negative for a concave lens)

• v = -10cm (image distance is negative for a virtual image)

• m = -(-10)/(-30) = -1/3