Things required : A Shoebox with black colour, tracing paper, a small object and a lamp.
Experiment : Colour the insides and the lid of the box with black colour. Cut a window on one side and paste a tracing paper on it to make the screen.
Make a small hole on the opposite side. Arrange the lamp, object and viewer. Light rays from lamp fall on object and then travel in straight lines and intersect each other as they travel through the viewer. An upside down image of the object is formed on the screen.
Things required : Three torches, pencil, transparent plastic sheets of red, green and blue colours and a round piece of card.
Experiment : Cover the three torches with the three transparent papers. If you mix Green and Red you make Yellow. Green and Blue together make Turquoise while Red and Blue make Purple. Divide the card into 7 equal parts and colour each with different colour of the spectrum. Rotate the disk after passing a pencil through the centre of this disk. All the colours will merge together to appear white showing you that white colour is made up of seven colours.