Question

In concave mirror if object is placed at 25 cm from pole on axis, its real image is obtained at 100 cm, so its magnification =​

Answer 1

Answer:

$\frac{1}{u} + \frac{1}{v } = \frac{1}{f}$

by using this formulla f=20

Explanation:

now using

$\binom{f - u}{f}$

you will get m=

$- \frac {1}{4}$