Question

The magnifying power of a simple microscope is 6. The focal length of its lens in metres will be, if least distance of distinct vision is 25$cm$

• A. 0.05
• B. 0.06
• C. 0.25
• D. 0.12

Answer 1

Answer: (A)

0.05

Answer 2

$m = 1 + \frac{D}{f} \Rightarrow 6 = 1 + \frac{25}{f} \Rightarrow f = 5\mspace{6mu} cm = 0.05\mspace{6mu} m$