A compound microscope with an objective of `1.0 cm` focal length and an eye piece of `2.0 cm` focal length has a tube length of `20 cm`. Calculate the magnifying power of microscope is final image is formed at the near point of eye.

Explanation

Here, `f_0 = 1.0 cm, f_e = 2.0 cm`,
`L = 20 cm, d = 25 cm`
When final image is formed at the near point of the eye (at least distance `d` of distinct vision), then
`m = (L)/(f_0)(1 + (d)/(f_e)) = (20)/(1.0)(1 + (25)/(2)) = 270`.