Physics

Problem

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

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}

187.5\,\text{cm}

18.75\,\text{cm}

300\,\text{cm}