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Question
(i) What is meant by resolving power of a telescope?
(ii) State any one method of increasing the resolving power of an astronomical telescope.
Solution
(i) Resolving power is the reciprocal of the smallest angular separation between two distant object which can be observed distinctly using a telescope.
If θ `[=(1.22lambda)/D]` be the angular separation, then resolving power = `1/theta = D/(1.22lambda)`;
[D =Aperture of objective lens]
(ii) By taking large aperture i.e., increasing the size of the aperture the resolving power of lens is increased.
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