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JEE Mains · Physics · STD 12 - 9. Ray optics and optical instruments
The focal length of the objective and the eyepiece of a telescope are \(50\,cm\) and \(5\,cm\) respectively. If the telescope is focussed for distinct vision on a scale distant \(2\,m\) from its objective, then its magnifying power will be
- A \(-4\)
- B \(-8\)
- C \(+8\)
- D \(-2\)
Answer & Solution
Correct Answer
(D) \(-2\)
Step-by-step Solution
Detailed explanation
Given: \(f_{0}=50\, \mathrm{cm}, f_{e}=5\, \mathrm{cm}\) \(\mathrm{d}=25\, \mathrm{cm}, \mathrm{u}_{0}=-200\, \mathrm{cm}\) Magnification \(\mathrm{M}=?\) As \(\frac{1}{\mathrm{v}_{0}}-\frac{1}{\mathrm{u}_{0}}=\frac{1}{\mathrm{f}_{0}}\)…
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