Question

a uniform metre rule restorers on city on a knife edge at the 60 centimetre mark when a mass of 10 gram is suspended from one end at which and must is must be suspended what is the mass of the rule
Explain with the help of diagram

Answer 1

Given,

A uniform meter rule is balanced at 60 cm.

Since, the knife is balanced at 60 cm the total anticlockwise moment is more than clockwise moment so to balance a mass of 10 g should be suspended at the end of to right hand side from 60 cm.

Let the mass of metre rule be x.

So, total anticlockwise moment = x * (60-50) g

Total clockwise moment = 10 g * (100-60)

= 10 * 40

= 400 g

By principle of moment we know,

Total anticlockwise moment = Total clockwise moment

x * 10 = 400

x = 400 \100

x = 40 g

So the mass of metre rule is 40 g.