ExamBro
ExamBro
TS EAMCET · Physics · Electrostatics

A screen is placed 90 cm from an object. The image is formed by using a convex lens twice on the screen by putting the lens at two different locations separated by 20 cm. The focal length of the lens is approximately equal to:

  1. A 21.38 cm
  2. B 30.0 cm
  3. C 35.0 cm
  4. D 24 cm
Verified Solution

Answer & Solution

Correct Answer

(A) 21.38 cm

Step-by-step Solution

Detailed explanation

The image of the object can be located on the screen for a two-position of convex lens such that, u and v are exchanged. The separation between two positions of the lens is, d= 20 cm From the figure, u1+v1=90 cm, v1-u1=20 cm, it means, v1=55 cm and…
Same subject
Explore more questions on app
From TS EAMCET
Explore more questions on app