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A body of mass 2 kg begins to move under the influence of time dependent force ⃗F=(2t̂i+6t²̂j) N, where ̂i and ̂j are unit vectors along x and y-axis respectively. The power produced by the force at t=2 s is ______ W.

Asked in JEE Main 4th April 1st Shift 2026 · Average and instantaneous power

Answer: 200

Step-by-step solution

⃗a=t̂i+3t²̂j; from rest ⃗v=(t²)/2̂i+t³̂j.

At t=2 s: ⃗F=4̂i+24̂j N, ⃗v=2̂i+8̂j m/s.

P=⃗F·⃗v=8+192=200 W.

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