## Question

A luminous object is placed at a distance of 30 cm from a convex lens of focal length 20 cm. On the other side of the lens, at what distance from the lens must a convex mirror of radius of curvature 10 cm be placed in order to have an upright image of the object coincident with it

### Solution

50 cm

This is possible when the rays are incident on the mirror normally, i.e., the image by the lens is formed at the centre of curvature of the mirror.

From figure, the distance of mirror from lens

#### SIMILAR QUESTIONS

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