Physics
When a boy weighing 20 kgf sits at one end of a 4m long see-saw, it gets depressed at its end. How can it be brought to the horizontal position by a man weighing 40 kgf.
Force
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Answer
As we know, the principle of moments states that
Anticlockwise moment = Clockwise moment
So it is proved that horizontal position can be achieved if a person sits at a distance of 1m from the centre on the side opposite to the boy.
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