A student wishes to design a reflecting telescope with a magnifying power of

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

Problem

75

. If the eyepiece available has a focal length of

2.5\,\text{cm}

, what should be the focal length of the primary mirror? (a)

75\,\text{cm}

(b)

187.5\,\text{cm}

(c)

18.75\,\text{cm}

(d)

300\,\text{cm}