Telescope

A small laboratory telescope has an objective lens of focal, length $140 cm$ and an eye-piece of focal length $6 cm$. Then, separation between the objective and eye-piece is _____.

The focal length of an objective of a telescope is 3 meter and diameter 15 cm. Assuming for a normal eye, the diameter of the pupil is 3 mm for its complete use, the focal length of eye piece must be

The power of objective and eye-piece is $5$ and $20$ dioptre respectively and the image is formed at infinity. Magnifying power of the telescope will be- 

Instrument that is used for seeing the moon, stars and planets.

Name the following.

An instrument for studying stars.

The eyepiece of a telescope has a higher focal length than the objective lens.

We can see far objects nearer with the help of _____.
(Choose from: microscope/periscope/telescope/kaleidoscope)

An astronomial telescope has an angular magnification of magnitude $5$ for distant object. The separation between the objective and the eye piece is $36 \mathrm{cm}$ and final image is formed at infinity. The focal length to the objective and focal length be for eye-piece are

An astronomical telescope has an angular magnification of magnitude 5 for distant objects. The separation between the objective and the eye-piece is 36 cm and the final image is formed at infinity. The focal length $f_0$ of the objective and the focal length $f_e$ of the eye-piece are

A Galilean telescope has an objective of focal length 100 cm and magnifying power 50. The distance between the two lenses in normal adjustment 

Focal length of objective and eyepiece of telescope are 200 cm and 4 cm respectively. What is length of telescope for normal adjustment?