## Question

A plano-concave lens is made of glass of refractive index 1.5 and the radius of curvature of the curved face is 50 cm. The power of the lens is

### Solution

Power = **–1 D.**

#### SIMILAR QUESTIONS

A small strip of plane mirror *A* is set with its plane normal to the principal axis of a convex mirror *B* and placed 15 cm in front of *B* which it partly covers. An object is placed 30 cm from *A* and the two virtual images formed by reflection in *A* and *B* concide without parallax. Find the radius of curvature of *B*.

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