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Question
Write the two important factors considered to increase the magnifying power?
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Solution
We can increase the magnifying power of telescope by
1. increasing the focal length of the objective
2. decreasing the focal length of eyepiece
Thus, two factor considered to increase the magnifying power are the focal lengths of objective and eyepiece.
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Assertion: An astronomical telescope has an objective lens having large focal length.
Reason: Magnifying power of an astronomical telescope varies directly with focal length of the objective lens.
