When a boy weighing 20 kgf sits at one end of a 4 m long see saw, it g

1.	When a boy weighing 20 kgf sits at one end of a 4 m long see saw, it gets depressed at this end. How can it be brought to the horizontal position by a man weighing 40 kgf.
Answer» From the principle of moments, Anticlockwise moment = Clockwise moment 20 kgf × 2m = 40kgf × d So, d = 20kgf x 2m/40kgf = 1m from the centre on the side opposite to the boy.

When a boy weighing 20 kgf sits at one end of a 4 m long see saw, it gets depressed at this end. How can it be brought to the horizontal position by a man weighing 40 kgf.

Answer»

From the principle of moments,

Anticlockwise moment = Clockwise moment

20 kgf × 2m = 40kgf × d

So, d = 20kgf x 2m/40kgf = 1m from the centre on the side opposite to the boy.