Describe the construction of a kaleidoscope.
A simple device is used to obtain the colorful designs by multiple reflections is called kaleidoscope.
Principle: It works on the principle of multiple reflection of light.
Construction:
- Get three rectangular plane mirror strips, each about 15 cm long and 4 cm wide.
- Join them together to form a prism.
- Pin them in a cylindrical cardboard tube, and make sure that the tube is slightly longer than the mirror strips.
- Close the one end of the tube by a cardboard disc having a hole in its center through which you can see.
- At the other end, touching the mirrors fix circular glass plate.
- Place several small pieces of the coloured glass on this glass plate.
- Close (disc) this end of the tube by ground glass plate. Allow enough space for the coloured pieces to move around. This is kaleidoscope.
When seen through the hole, we will be able to see a variety of patterns in the tube.
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