WBJEE · Physics · Ray Optics
If the focal length of the eye piece of a telescope is doubled, its magnifying power \((\mathrm{m})\) will be
- A \(2 \mathrm{~m}\)
- B \(3 \mathrm{~m}\)
- C \(\frac{\mathrm{m}}{2}\)
- D \(4 \mathrm{~m}\)
Answer & Solution
Correct Answer
(C) \(\frac{\mathrm{m}}{2}\)
Step-by-step Solution
Detailed explanation
Hints: \(\mathrm{m}=\frac{-\mathrm{f}_0}{\mathrm{f}_{\mathrm{e}}}\) \(\mathrm{m}^{\prime}=\frac{\mathrm{m}}{2}\)
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