Explain the working of an astronomical telescope using refraction of light.

Explanation

Telescope is used to see distant objects clearly in their magnified form. The telescopes used to observe astronomical sources like the stars and the planets are called astronomical telescopes.
(ii)Objective lens has large diameter and larger focal length because of which maximum amount of light coming from the distant object can be collected.
(iii)On the other hand the size of the eyepiece is smaller and its focal length is also less. Both the lenses are fitted inside a metallic tube in such a way that the distance between them can be changed.
(iv)When rays of light enter the objective, they refract and give a real inverted and diminished image.
(v) The eye-piece is so adjusted that the image becomes an object for the eyepiece and gives a virtual, enlarged and inverted image w.r.t to object.