Question

In astronomical telescope, the final image is formed at:

• A. the least distance of distinct vision
• B. the focus of objective lens
• C. the focus of the eye lens
• D. beyond the focal length of eyepiece.

Answer 1

Answer: (D)

beyond the focal length of eyepiece.

In astronomical telescope, the image formed by objective $I_1$ is real and inverted. It is formed at focus of objective lens. $I_1$ is placed between the focal length of eyepiece and the lens. Hence, it forms a virtual image beyond the focal length of eyepiece.