MENU

A concave lens of focal length f forms an image which is 1/3 times the size

A Concave Lens Of Focal Length F Forms An Image Physics Question

A concave lens of focal length f forms an image which is 1/3 times the size of the object. Then, the distance of object from the lens is

Options

(a) 2f
(b) f
(c) 2/3f
(d) 3/2f

Correct Answer:

2f

Explanation:

Given, f = -f ⇒ v = (1/3)u

According to the lens formula, 1/f = (1/v) – (1/u) – (1/f)

= [1/(-1/2)u] + (1/u) – (1/f) 1/f

= [(-3+1)/u] – (1/f)

= -2/u ⇒ u = 2f

Related Questions:

  1. A projectile is fired at 30°. Neglecting friction, the change in kinetic energy when
  2. An electric dipole placed in a non-uniform electric field experiences
  3. A proton is moving in a uniform magnetic field B in a circular path of radius a
  4. An air bubble in a glass slab with refractive index 1.5 (near normal incidence)
  5. The temperature coefficient of a resistance wire is 0.00125 per degree.

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Your email address will not be published.


*