For a distant object,the angular magnification of an astronomical telescope is $5$. The distance between the objective and the eyepiece is $36 \, cm$,and the final image is formed at infinity. What are the focal lengths of the objective $(f_o)$ and the eyepiece $(f_e)$?

  • A
    $f_o = 45 \, cm$ and $f_e = -9 \, cm$
  • B
    $f_o = 50 \, cm$ and $f_e = 10 \, cm$
  • C
    $f_o = 7.2 \, cm$ and $f_e = 5 \, cm$
  • D
    $f_o = 30 \, cm$ and $f_e = 6 \, cm$

Explore More

Similar Questions

$A$ telescope has an eyepiece of focal length $5\, cm$ and an objective lens of focal length $60\, cm$. It is focused on a distant object such that the rays emerge from the eyepiece as parallel rays. Find the angular width of the image in degrees $(^o)$ if the object subtends an angle of $2^o$ at the objective.

The final image formed by an astronomical telescope is

$A$ reflecting telescope has a large mirror as its objective with a radius of curvature equal to $80 \, cm$. What is the magnifying power of this telescope if the eyepiece used has a focal length of $1.6 \, cm$?

In an astronomical telescope,the focal lengths of two lenses are $180 \, cm$ and $6 \, cm$ respectively. In normal adjustment,the magnifying power will be

An astronomical refracting telescope will have large angular magnification and high angular resolution when it has an objective lens of

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo