Class 12th Physics 2017 Set1 Delhi Board Paper Solution
Define the magnifying power of a compound microscope when the final image is formed at infinity. Why must both the objective and the eyepiece of a compound microscope has short focal lengths? Explain.
Angular magnification or magnifying power of compound microscope is defined as ratio of angle made at eye by image formed at infinity to the angle made by object, if placed at distance of distinct vision from an unaided eye.
Magnification = LD / f0 . fe
where, L-length of the tube of microscope
As, m ∝ 1/f0
and m ∝ 1 / fe
∴ both eye piece and objective must be of smaller focal lengths, so, that magnification is higher.
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