Home
Class 11
PHYSICS
The magnifying power of a telescope is 1...

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 ?

A

20

B

30

C

40

D

50

Text Solution

Verified by Experts

The correct Answer is:
C
`M.P. =(f_(o))/(f_(e))=10`
New `M.P. =(f_(o)^('))/(f_(e)^('))=(2f_(o))/((f_(e))/(2))=4((f_(o))/(f_(e)))=4xx10=40`
Promotional Banner

Topper's Solved these Questions

  • RAY OPTICS (MIRRORS, LENSES AND OPTICAL INSTRUMENTS)

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP|10 Videos

  • MEASUREMENTS

    MARVEL PUBLICATION|Exercise TEST YOUR GRASP|10 Videos

  • REFRACTION OF LIGHT

    MARVEL PUBLICATION|Exercise Test Your Grasp|10 Videos

Similar Questions

Explore conceptually related problems

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

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 -

An astronomical telescope has a magnifying power 10. The focal length of eyepiece is 20 cm . The focal length of objective is

The magnifying power of terrestrial telescope is 25 when it is in normal adjustment and the length of the telescope is 124 cm. If the focal length of the erecting lens is 5 cm, the focal lengths of the objective and the eye-piece are respectively.

The magnifying power of a telescope is 9. When it is adjusted for parallel rays the distance between the objective and eyepiece is 20cm . The focal lengths of lenses are

The magnifying power of a microscope with an objective of 5 mm focal length is 400. The length of its tube is 20cm. Then the focal length of the eye - piece is