Materials required: -an old post card and scissors.

Some of the tribes in India have a kind of short bent stick. In Australia too the hill tribes used a similar one to hunt the birds. This is called the" Boomerang". You can also do and see it.
Take the card and cut  out a right angle with arms about 3 cm. long and about 1/2 cm. 44/a ,breadth. Round off the sharp corners with sci­ssors. Place this piece on broad card holding it slightly tilted upwards, and the two arms sticking out. Give a click to one of the arms. See how it soars in the air spiraling away and returns back to you.
It is true. How does it happen? The circling card goes up against gravity. After sometime it has lost its momentum and there is no more force to resist the gravitational pull.
Therefore, it finds its easy way to return in the same spiral manner.

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