Q. 35.0( 1 Vote )

A simple microscope has a magnifying power of 3.0 when the image is formed at the near point (25 cm) of a normal eye. (a) What is its focal length? (b) What will be its magnifying power if the image is formed at infinity?

Answer :

Given data-

Magnifying power of microscope, m = 3.0

Least distance of clear vision, D = 25 cm

a. If the image is formed at D which is equal to 25cm, then the magnifying power is given by

Hence the focal length when the image is formed at 25cm is 12.5cm

b. If the image is formed at infinity, the magnifying power of the lens becomes-

Hence the magnifying power becomes 2.0 when the image is formed at infinity

Rate this question :

How useful is this solution?
We strive to provide quality solutions. Please rate us to serve you better.
Try our Mini CourseMaster Important Topics in 7 DaysLearn from IITians, NITians, Doctors & Academic Experts
Dedicated counsellor for each student
24X7 Doubt Resolution
Daily Report Card
Detailed Performance Evaluation
view all courses