JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
If we need a magnification of \(375\) from a compound microscope of tube length \(150\; \mathrm{mm}\) and an objective of focal length \(5\; \mathrm{mm}\), the focal length of the eye-piece, should be close to.....\(mm\)
- A \(22\)
- B \(12\)
- C \(33\)
- D \(2\)
Answer & Solution
Correct Answer
(A) \(22\)
Step-by-step Solution
Detailed explanation
\(M =\frac{ v _{0}}{+ u _{0}}\left(1+\frac{ d }{ fe }\right)\) focal length of objective lens is small \(u_{0} \simeq f _{0}\). Alos as focal length of eye is small \(v _{0} \simeq L\) \( M =\frac{ L }{+ f _{0}}\left(1+\frac{ d }{ f _{ e }}\right) \)…
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