$A$ telescope has an objective of focal length $100 \ cm$ and an eye-piece of focal length $5 \ cm$. The magnifying power of the telescope is

$A$ Galileo telescope has an objective of focal length $100 \, cm$ and magnifying power $50$. The distance between the two lenses in normal adjustment will be....$cm$

$A$ telescope has an objective of focal length $100 \ cm$ and an eyepiece of focal length $5 \ cm$. The least distance of distinct vision is $25 \ cm$. The telescope is focused for distinct vision on a scale $3 \ m$ away from the objective. The magnification produced is . . . . . .

The magnifying power of an astronomical telescope is $8$ and the distance between the two lenses is $54 \, cm$. The focal lengths of the eye lens and the objective lens will be respectively:

What is the tube length of a telescope?

If the focal length of the objective lens is increased,then: