Question

describe an activity to show that white light is made of seven colours

Answer 1

Light is made up of wavelengths of light, and each wavelength is a particular colour. The colour we see is a result of which wavelengths are reflected back to our eyes.Visible light waves consist of different wavelengths. The colour of visible light depends on its wavelength. These wavelengths range from 700 nm at the red end of the spectrum to 400 nm at the violet end.

White light is actually made of all of the colours of the rainbowbecause it contains all wavelengths, and it is described as polychromatic light. Light from a torch or the Sun is a good example of this.

hope help...

Answer 2

cut a circle of radius 10cm from cardboard
paint it with seven colours {in rainbow}
make a small hole in the centre
take a ball pint ink and fit disc into it
rotate it into the sunlight 



you will see white light in it