Question

A uniform half metre rule can be balanced at the 29.0 CM when a mass 20 gram is hung from its one end. *draw diagram of the arrangement *find the mass of the half metre rule *in which direction would the balancing. Shift if 20 gram mass is shifted inside from its one end ​

Answer 1

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