Colour of objects in white light
When white light falls on any particular body, then either all the colours in the white light may be reflected from the body, when it appears white, or only some of them may be reflected while the others are absorbed. In the latter case the body appears coloured. The energy of the light absorbed is generally converted into internal energy so that the body becomes slightly warmer. The colour which the body presents to the eye is the colour of the light which it reflects. Thus the leaves of plants appear green, since they reflect green light and absorb the other colours. White paper reflects all the colours of the spectrum while black paper absorbs all of them. Blackness is thus due to the absence of light of any colour.