To Find The Mass Of A Given Body Using A Metre Scale By Principle Of Moments - Practice Questions & MCQ

Aim-
To determine mass of a given body using a metre scale by principle of moments.

Apparatus-
A metre scale, a broad heavy wedge with sharp edge, a weight box, a body of unknown mass.

Theory -

If m and M be the mass of the body and mass of the weight used and a and A be the distances of their loops from wedge. Then, power (mass) arm =a, weight arm =A
From principle of moments m.g.a=M.g.A

m= mass of body

M= mass of weight

A= distance from wedge

Calculation

Procedure: 

1.    Arrange the meter scale in a horizontal position by supporting it at 50 cm mark at the sharp edge of the broad heavy wedge.    

2.    Take a loop thread.

3.    Suspended the given body whose mass is to be determined by the loop thread at a fixed mark on the left of the wedge.

4.    Suspended a paper pan on the right side of the wedge.

5.    Put some known weight in the pan.

Result
The unknown mass of the body, .

Precautons -

1. The wedge should be broad and heavy with sharp edge.
2. Metre scale should have uniform mass distribution.
3. Threads used for loops should be thin, light and strong,