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Question
A metre scale of weight 50 gf can be balanced at 40 cm mark without any weight suspended on it.
- If this ruler is cut at its centre then state which part [0 to 50 cm or 50 to 100 cm] of the ruler will weigh more than 25 gf.
- What minimum weight placed on this metre ruler can balance this ruler when it is pivoted at its centre?
Solution
a. Because the scale of meters is not uniform, 0 to 50 cm would be heavier.
b. By principle of moments
50 × 10 = w × 50
w = 10 gf
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