When an object is placed 40cm from a diverging lens, its virtual image is formed 20 cm

When An Object Is Placed 40cm From A Diverging Lens Physics Question

When an object is placed 40cm from a diverging lens, its virtual image is formed 20 cm from the lens. The focal length and power of lens are

Options

(a) F=-20 cm, P=-5 D
(b) F=-40 cm, P=-5 D
(c) F=-40 cm, P=-2.5 D
(d) F=-20 cm, P=-2.5 D

Correct Answer:

F=-40 cm, P=-2.5 D

Explanation:

We have, 1 / f = (1/v) – (1/u) ⇒ 1 / f = (1/-20) – (-1/40) = (-1 + 1) / 40 = 1 / 40

f = – 40 cm

Power of the lens, P = – (200 / 0.40) = – 2.5 D

Related Questions:

  1. The self-inductance of a coil having 500 turns is 50mH. The magnetic flux
  2. A particle of mass m is projected with velocity v making an angle of 45° with
  3. A bullet is shot from a riffle. As a result the rifle recoils.The kinetic energy of riffle
  4. The minimum wavelength of X-rays emitted by X-ray tube is 0.4125Å
  5. If in a p-n junction, a square input signal of 10 V is applied as shown, then the output

Topics: Ray Optics (94)
Subject: Physics (2479)

Important MCQs Based on Medical Entrance Examinations To Improve Your NEET Score

18000+ students are using NEETLab to improve their score. What about you?

Solve Previous Year MCQs, Mock Tests, Topicwise Practice Tests, Identify Weak Topics, Formula Flash cards and much more is available in NEETLab Android App to improve your NEET score.

NEETLab Mobile App

Share this page with your friends

Be the first to comment

Leave a Reply

Your email address will not be published.


*