JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(2\) kg begins to move under the influence of time dependent force \(\vec{F} = (2t\hat{i} + 6t^2\hat{j})\) N, where \(\hat{i}\) and \(\hat{j}\) are unit vectors along \(x\) and \(y\)-axis respectively. The power produced by the force at \(t = 2\) s is _____ W.
- A 200
- B 205
- C 210
- D 220
Answer & Solution
Correct Answer
(A) 200
Step-by-step Solution
Detailed explanation
Given \(\vec{F} = (2t\hat{i} + 6t^2\hat{j})\) N and \(m = 2\) kg. Acceleration of the body is \(\vec{a} = \dfrac{\vec{F}}{m} = \dfrac{2t\hat{i} + 6t^2\hat{j}}{2} = t\hat{i} + 3t^2\hat{j}\) m/s\(^2\). Since the body begins to move from rest, its velocity at time \(t\) is given by…
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