Colours

COLOURS

The colour white is composed by 7 different colour components, also known as the 7 colours of the rainbow. Thus when white light is shone onto a prism, a spectrum of seven colour components will be dispersed as shown below.

This situation can be reversed by placing another prism with the vertices and bases in opposite directions as shown below.

Primary colours are red, green and blue.

 Secondary colours include: 

-Yellow (red + green),

-Magenta (red + blue), 

-Cyan (green + blue).

A leaf appears green to an observer. When white light strikes a leaf, only green light is reflected to the observer. The rest of the colours is absorbed by the leaf. Therefore, the leaf appears green to the observer. From this example, we can see that the colour of an object depends on the colour of light being reflected to the observer.