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Question
A uniform metre scale can be balanced at the 70.0 cm mark when a mark when a mass 0.05 kg is hung from the 94.0 cm mark
- draw a diagram of the arrangement
- Find the mass of the metre scale
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Solution
1) A diagram of the given arrangement is shown below.
2) As the given meter scale is a uniform scale. So its centre of gravity lies at 50 cm. Let the mass of the meter-scale be W1 kg.
From the principle of moments
Anticlockwise moment = clockwise moment
m1x1 = m2x2
m1 × (70 − 50) = 0.05 × (94 − 70)
m1 = `(0.05 xx 24)/20`
= 0.06 kg
= 60 g
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