Question

The magnifying power of an astronomical telescope is 20. If the focal length of objective is 80 cm, what is the focal length the of the eye-piece when image is formed at a distance of distinct vision ?
plz answer​

Answer 1

Answer:

Solution

verified

Correct option is D)

Given,

Focal length of objective, f

0

=50

Focal length of eye-piece, f

e

=5

Length of telescope, L=?

L=f

0

+

D+f

e

Df

e

=50+

30

25×5

=

6

325

cm