When we enter a dark room coming from outside,  immediately the things inside the room do not  appear clear to our eyes. This is because  

(a) pupils do not open at all in the dark.  

(b) pupils take time to adjust.  

(c) light travels slower in a dark room.  

(d) pupils open very quickly in the dark.  

 

Answer

 

  • When we enter a dark room coming  from outside, immediately the things inside the room do not appear clear to our eyes.
  • This is because  pupils take time to adjust
  • Pupil is a hole in the middle of the iris , which appears black because the light that passes through it gets absorbed by the retina and is not reflected back .
  • Thus, when it’s dark, pupil becomes big so as to absorb more light from the environment

Pupil dilates in bright light,  and contracts in dim light_- Teachoo.jpg

So, the correct answer is (b) - pupils take time to adjust  

  1. Class 10
  2. Chapter 11 Class 10 - Human Eye and Colourful World (Term 1)

About the Author

CA Maninder Singh's photo - Founder at Teachoo
CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 11 years and a teacher from the past 11 years. He teaches Science, Accounts and English at Teachoo