Question

A uniform metre scale balances horizontally at 44 cm mark when a weight of 20 g is placed at 15 cm mark. What is weight of metre scale? Draw a diagram of arrangement.

Answer 1

(i) Diagram of the given arrangement is shown below.

(ii) As the given meter scale is a uniform scale. So its centre of gravity lies at 50 cm. Let mass of meter scale be W1 kg.

By principle of moments,

m1x1 = m2x2

m1 x (70 - 50) = 0.05 x (94 - 70)

m1 = 0.05 x 24/20

= 0.06 kg.

= 60 gm.