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Question
A child has near point at 10 cm. What is the maximum angular magnification the child can have with a convex lens of focal length 10 cm?
Solution
Given:
Distance of near point, D = 10 cm
Focal length, f = 10 cm
When the image is formed at the near point, D = 10 cm, the magnifying power (m) of a simple microscope is given as:
` m = 1+D/f`
= `1+10/10 = 1+1 =2`
Thus, the maximum angular magnification is 2.
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