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A small telescope has an objective lens ...

A small telescope has an objective lens of focal length 140cm and an eyepiece of focal length 5.0cm. What is the magnifying power of the telescope for viewing distant objects when
(a) the telescope is in normal adjustment (i.e., when the final image is at infinity)?
(b) the final image is formed at the least distance of distinct vision (25cm)?

A

0.036

B

28

C

135

D

145

Text Solution

Verified by Experts

The correct Answer is:
B

28
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KUMAR PRAKASHAN-RAY OPTICS AND OPTICAL INSTRUMENTS-SECTION-D (MULTIPLE CHOICE QUESTIONS (MCQs))(MCQs FROM .DARPAN. BASED ON TEXTBOOK)(MCQs BASED ON TEXTUAL ILLUSTRATION AND EXERCISE)
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  9. A small telescope has an objective lens of focal length 144cm and an e...

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  11. (a) A giant refracting telescope at an observatory has an objective le...

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  14. A screen is placed 90cm from an object. The image of the object on the...

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  17. A small telescope has an objective lens of focal length 140cm and an e...

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