Question

a uniform metre scale rests horizontally on a knife edge at the 60cm mark when a mass of 10 gram is suspended from one end . at which end this mass be suspended . what is the mass of meter scale?

Answer 1

40 gram or 0.04 kilogram

Step-by-step explanation:

From the diagram attached,

The mass must be suspended at end B.

Applying the principle of moment,

Sum of clockwise moment = sum of anti-clockwise moment.

From the diagram,

Taking the moment about the pivot,

X(60-50) = 0.1(100-60)

Where X = weigth of the meter rule

10X = 4

X = 4/10

X = 0.4 N

X = 0.4/10

X = 0.04 kg

X = 40 g

Hence the mass of the meter rule = 0.04 kg or 40 gram