ExamBro
ExamBro
AP EAMCET · PHYSICS · Ray Optics

A screen is placed \(100 \mathrm{~cm}\) from an object. The image of the object on the screen is formed by a convex lens at two different locations separated by \(20 \mathrm{~cm}\). The focal length of the lens is

  1. A \(18 \mathrm{~cm}\)
  2. B \(24 \mathrm{~cm}\)
  3. C \(25 \mathrm{~cm}\)
  4. D \(30 \mathrm{~cm}\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(24 \mathrm{~cm}\)

Step-by-step Solution

Detailed explanation

Given, distance between screen and object, \(d=100 \mathrm{~cm}\) Separation between the two pośitions of convex lens, \(\quad x=20 \mathrm{~cm}\) focal length of the lens, \(f=\frac{d^2-x^2}{4 d}\)…
Same subject
Explore more questions on app