Get Answers to all your Questions

header-bg qa

The focal length of an equiconcave lens is \frac{3}{4} times of radius of curvature of its surfaces. Find the refractive index of the material of the lens. Under what condition will this lens behave as a converging lens ?

 

 
 
 
 
 

Answers (1)

\frac{1}{f}=(n-1)[\frac{1}{R_1}-\frac{1}{R_2}]

\\R_1=-R\\R_2=R

\\\frac{-4}{3R}=(n-1)[\frac{-2}{R}]\\implies\\n-1=\frac{2}{3}\\\\n=\frac{5}{3}

If the lens is immersed in a medium of refractive index greater than 5/3 , it will behave like a converging lens

Posted by

Safeer PP

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads