Physicshard · Past Paper

A point object is placed 10 cm from a convex lens of focal length 20 cm. The image formed is:

AReal and 20 cm away
BVirtual and 20 cm away
CVirtual and 10 cm away
DReal and 10 cm away

✓ Correct Answer: BVirtual and 20 cm away

1/v = 1/20 + 1/(-10) = (1-2)/20 = -1/20. So v = -20 cm (virtual).

Share this question

More from Physics