Question

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

Answer 1

Answer:

A parallel beam of rays from an astronomical object is made to fall on the objective lens of the telescope. It forms a real, inverted and diminished image A′B′ of the object. ... Therefore, a highly magnified image of the object is formed at infinity.

Answer 2

Answer:

The astronomical telescope consists of two lenses: objective and eyepiece. Objective has larger focal length and diameter to accommodate maximum amount of light coming from the far away (astronomical) objects. A parallel beam of rays from an astronomical object is made to fall on the objective lens of the telescope. It forms a real, inverted and diminished image A

′

B

′

of the object. The eyepiece is so adjusted that A

′

B

′

lies just at the focus of the eye piece. Therefore, a highly magnified image of the object is formed at infinity. The same has been shown in the figure below.