Question

a uniform rule of unknown length is balanced at a distance of 20 cm from one end . A weight of 120 gf is suspended from this end. Calculate the length of the metre rule if its weight is 80 gf. ​

Answer 1

Hello Dear.

Here is the answer---

•¶ Refers to the attachment for the Question.

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 105 gf.

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

°°°°°°°°°°°=°°°°°°°°°°°°°

•Hope it helps.•

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