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प्रश्न
A block of mass 2 kg placed on a long frictionless horizontal table is pulled horizontally by a constant force F. It is found to move 10 m in the first seconds. Find the magnitude of F.
उत्तर
Given:
Mass of the block, m = 2 kg,
Distance covered, S = 10 m and initial velocity, u = 0
Let a be the acceleration of the block.
Using, `S = ut + 1/2at^2`
`10 = 1/2a(1^2)`
⇒ a = 20 m/s2
∴ Force, F = ma = 2 × 20 = 40 N
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