Question

Compound microscope has magnification $30$. Focal length of eyepiece is $5cm$ and final image is formed at least distance of distinct vision. Find magnification of objective.

Answer 1

Here in this case, $\mu =-30,f_e=5cm,D=25cm$

Now $\mu ={\mu }_0\times {\mu }_e={\mu }_0\times (1+\frac{D}{f_e})$

$-30={\mu }_0[1+\frac{25}{5}]$

${\mu }_0=-2$