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Question
A uniform metre rule of weight 10 gf is pivoted at its 0 mark.
- What moment of force depresses the rule?
- How can it be made horizontal by applying a least force?
Solution
Weight of metre scale = 10 gf
- Moment of force = 10 × 50 cm = 500 gf cm
- It can be made horizontal by a moment of force = 500 gf cm
500 = w × 100
∴ w = `500/100`
= 5 gf cm
By applying 5 gf upward at the 100 cm mark.
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