A 10 kg load hangs 0.5 m from the pivot of a light uniform lever. What force at 4 m on the other side of the pivot balances it? (take g = 10 m/s²)
Answer and explanation
Correct answer: D. 12.5 N
- Step 1: Take moments about the pivot: F × 4 = 10 × 10 × 0.5. Step 2. F = 12.5 N. Answer: 12.5 N. Why not the others: 100 N is what you get if you ignore the distances. 800 N is what you get if you swap the two distances. 50 N is what you get if you forget to divide by the second distance.
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