Question

A half metre ruler scale having weight 30gf suspended at one end and fulcrum at 29cm what is the weight of the ruler if ruler is balanced

Answer 1

Explanation:

ANSWER

Let the weight of the half metre rule be x gf and it acts at the 25 cm mark (centre of gravity).

Now,

Acticlockwise moment = x×4

Clockwise moment = 20×21

In equilibrium,

Anticlockwise moment = Clockwise moment

4x=20×21

x=105 gf.

Thus, the weight of the metre rule is 105gf.

We know, one gf is the force acting on the body of mass 1 grams, thus mass of the body is 105grams.