When the final image is formed at infinity

PHYSICS · Single correct · CBSE · Physics · Ray Optics and Optical Instruments · Ray Optics and Optical Instruments

Problem

When the final image is formed at infinity, the magnifying power of a simple magnifier is given by (a)

m = \dfrac{f}{D}

(b)

m = \dfrac{D}{f}

(c)

m = 1 + \dfrac{D}{f}

(d)

m = \dfrac{D}{2f}