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Question
Define the magnifying power?
Solution
Magnifying power of refracting telescope (M) is defined as the ratio of the angle subtended by the image (β) at the eye to the angle subtended by the distant object at the unaided eye (α).
`M= β/a`
Where
β = Angle subtended by the image at the eye.
α = Angle subtended by the distant object at the unaided eye.
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