Question

How is the working of a telescope different from that of a microscope ? The focal lengths of the objective and eyepiece of a microscope are 1.25 cm and 5 cm respectively. Find the position of the object relative to the objective lens in order to obtain an angular magnification of 30 in normal adjustment.

Answer 1

Working differences :

(i) The objective of a telescope forms the image of a very far off object at. or within, the focus of its eyepiece. The microscope does the same for a small object kept just beyond the focus of its objective.

(ii) The final image formed a telescope is magnified relative to its size as seen by the unaided eye, while the final image formed by a microscope is magnified relative to its absolute size. 

(iii) The objective of a telescope has large focal length and large aperture, while the corresponding for a microscope have very small values.