the human eye

A person having a myopic eye used the concave lens of focal length 50cm. What is the power of the lens?


(a)  

How does the eye adjust itself to deal with light of varying intensity?



(a)  

How do we see colours?



(a)  

How does the eye adjust its focal length?



(a)  

Why is the colour of the clear sky blue?



(a)  

The sky appears dark instead of blue to an astronaut. State its reason.

(a)  

Which phenomenon is responsible for making the path of light visible?

(a)  

What is the cause of dispersion of white light on passing through a prism?

(a)  

Why is red colour selected for danger signal lights?

(a)  

Why do different components of white light deviate through different angles when passing through a triangular glass prism?

(a)