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Question
Two unlike forces (parallel) of 10 N and 25 N act at a distance of 12 cm. from each other. Find the point about which the body balance.
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Solution
Let the balance be at x cm from the 25 N force.
Anti-clockwise moment = 10 (12 − x)
Clockwise moment = 25 x
Applying the principle of moments,
⇒ 10 (12 − x) = 25 x
⇒ 120 − 10 x = 25 x
⇒ 35 x = 120
⇒ x = `120/35`
= 3.43 cm.
∴ The body balances at the 3.43 cm mark.
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