Question

The angular magnification of telescope is $30$. If all the light which passes through objective lens of diameter $80cm$ also passes through eye piece lens then find out diameter of eye piece lens.

• A. $\frac{1}{4}cm$
• B. $\frac{3}{8}cm$
• C. $\frac{8}{3}cm$
• D. $\frac{1}{5}cm$

Answer 1

The correct option is C $\frac{8}{3}cm$

magnificant of telescope M diameter of objective d0 diameter of eyelens dE $M=\frac{d0}{dE}$

$dE=\frac{d0}{M}=\frac{80}{30}=\frac{8}{3}$