Question

A compound microscope has a magnification of 30. The focal length of eye piece is 5 cm. Assuming the final image to be at least distance of distinct vision, find the magnification produced by the objective

Answer 1

Magnification of compound microscope, M = 30 Focal length, f = 5 cm Least distance of distinct vision, D = 25 cm Now, 

M = M₀ xM_e

= M₀ x [1 + \(\frac{D}{f_e}\)_]

30 = M₀ x [1 + \(\frac{25}{5}\)]

M₀ = \(\frac{30}{6}\) = 5