Observe the colours of light coming out of the CD through filters of different colours and record your observations in your science diary.

The principal behind this type of phenomena is that the filters only allow certain colour to pass and block the others. For example, the red filter will only allow the red colour to pass through it and will block the other colour. One more example is of yellow filter, in this case the filter will allow yellow as well as red and green colour light because red and green are constituents of yellow colour.

All the colour observed are same as of filter colour or its constituents.