Draw a diagram to show how white light can be dispersed into a spectrum by using a glass prism. Mark the various colours of the spectrum.

When a beam of white light is passed through a prism, it splits to form lights of seven colours. Is it possible to recombine the lights of seven colours to obtain the white light again? Explain your answer.

Which is refracted most by a prism: red light or violet light? Explain why?

Write the function of each of the following parts of human eye.

1. Cornea.
2. Iris.
3. Crystalline lens.
4. Ciliary muscles.

Draw ray diagrams each showing:Hypermetropic eye.

The picture given here shows a person wearing 'half-moon' spectacles. What sort of eye-defect do do you think he has? Why are these particular spectacles useful to him?

How does the convex eye-lens differ from the ordinary convex lens made of glass?

In a certain murder investigation, it was important to discover whether the victim was long-sighted or short-sighted. How could a detective decide by examining his spectacles?

Draw a labelled ray diagram to illustrate the dispersion of a narrow beam of white light when it passes through glass prism.

A person can comfortably read a book but finds it difficult to read the number on a bus parked 5 m away from him. Name the type of defect of vision he is suffering
from. Which type of lens should be used in his spectacles to correct his vision?