To increase the magnifying power of telescope ( `f_(o)` = focal length of the objective and `f_(e)` = focal length of the eye lens)

The length of an astronomical telescope for normal vision (relaxed eye) ( f_(o) = focal length of objective lens and f_(e) = focal length of eye lens) is

The length of an astronomical telescope for normal vision (relaxed eye) ( f_(o) = focal length of objective lens and f_(e) = focal length of eye lens) is

The magnifying power of a telescope is 10. What would be its new magnifying power if the focal length of the objective is doubled and the focal length of the eyepiece is halved ?

The focal length of the objective of an astronomical telescope is 1.0 m. If the magnifying power of the telescope is 20, find the focal length of the eyepiece and the length of the telescope for the relaxed eye.

An astronomical telescope has a magnifying power 10. The focal length of the eye piece is 20 cm. the focal length of the objective is -