Force — Question 15

As we know, the principle of moments states that

Anticlockwise moment = Clockwise moment

$100gf \times 40cm = W \times 60cm$

Weight on the longer pan

$W = \dfrac{(100 \times 40) }{60} \\[0.5em] W = 66.67gf$

So, a weight of 66.67gf kept on the pan of longer arm will balance the object of weight 100 gf kept on the other pan.