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Question
Define the term 'resolving power of a telescope'. How will the resolving power be effected with the increase in
(i) Wavelength of light used.
(ii) Diameter of the objective lens.
Solution
The resolving power of an astronomical telescope is defined as the reciprocal of the smallest angular separation between two point objects whose images can just be resolved by the telescope.
`R.P = (1.22lambda)/D`
With the increase in wavelength of light, the resolving power increases whereas, with the increase in the diameter of the lens, the resolving power decreases.
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| 1 | Charge of a proton | e | 1.6 × 10-19 C |
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| 1 u = 931 MeV | |||
