JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
In a compound microscope the focal length of objective lens is \(1.2\, cm\) and focal length of eye piece is \(3.0\, cm\). When object is kept at \(1.25\, cm\) in front of objective, final image is formed at infinity. Magnifying power of the compound microscope should be
- A \(200\)
- B \(100\)
- C \(400\)
- D \(150\)
Answer & Solution
Correct Answer
(A) \(200\)
Step-by-step Solution
Detailed explanation
Given \(: f_{0}=1.2\, \mathrm{cm} ; f_{\mathrm{e}}=3.0 \,\mathrm{cm}\) \(u_{0}=1.25\, \mathrm{cm} ; M_{\infty}=?\) From \(\frac{1}{f_{0}}=\frac{1}{v_{0}}-\frac{1}{u_{0}}\) \(\Rightarrow \frac{1}{1.2}=\frac{1}{v_{0}}-\frac{1}{(-1.25)}\)…
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