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प्रश्न
A force acts for 0.1 s on a body of mass 2.0 kg initially at rest. The force is then withdrawn and the body moves with a velocity of 2 m s-1. Find the magnitude of the force.
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उत्तर
Mass, m = 2.0 kg i.e. 2 kg
Initial velocity, u = 0
Final velocity, v = 2 m/s
Time, t = 0.1 s
Acceleration = `"Change in velocity"/"time"`
∴ a = `("v" - "u")/"t"`
∴ a = `(2 - 0)/0.1`
∴ a = 20 ms-2.
Force = Mass × Acceleration
⇒ F = 2 × 20
∴ F = 40 N.
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