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Question
Define magnifying power of a telescope. Write its expression.
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Solution
Magnifying power of a telescope is defined as the ratio of the angle subtended at the eye by the image formed at the least distance of distinct vision to the angle subtended at the eye by the object lying at infinity, when seen directly.
The formula for magnifying power is,
Magnifiying power,`M = - f_0/f_e (1 + f_e/D)`
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