Physics 2018 JAMB Past Questions - Question 9: A narrow beam of white light can be split up into different colours by a glass prism. The correct explanation is that

Correct Answer

C

Explanation

 when white light passes through a glass prism, it undergoes a process called refraction. Refraction occurs because light travels at different speeds in different mediums, such as air and glass.

When white light enters the prism, it slows down and bends, or refracts, as it passes from air to glass. The amount of bending depends on the wavelength of the light. Different wavelengths of light correspond to different colors.

As the white light passes through the prism, the different colors that make up the white light bend at slightly different angles due to their different wavelengths. This causes the light to spread out, or disperse, into a spectrum of colors, known as a rainbow.

The longer wavelengths, such as red, bend the least, while the shorter wavelengths, such as violet, bend the most. The other colors, such as orange, yellow, green, and blue, bend at varying degrees between red and violet.

This separation of colors is what allows us to see the different colors of the spectrum when white light passes through a glass prism.