JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
A body of mass \(2 \mathrm{~kg}\) begins to move under the action of a time dependent force given by \(\overrightarrow{\mathrm{F}}=\left(6 \mathrm{t} \hat{\mathrm{i}}+6 \mathrm{t}^2 \hat{\mathrm{j}}\right) \mathrm{N}\). The Power developed by the force at the time \(t\) is given by _______.
- A \(\left(6 t^4+9 t^5\right)\ \mathrm{W}\)
- B \(\left(3 t^3+6 t^5\right)\ W\)
- C \(\left(9 t^5+6 t^3\right)\ \mathrm{W}\)
- D \(\left(9 t^3+6 t^5\right)\ W\)
Answer & Solution
Correct Answer
(D) \(\left(9 t^3+6 t^5\right)\ W\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{\mathrm{F}}=\left(6 \mathrm{t} \hat{\mathrm{i}}+6 \mathrm{t}^2 \hat{\mathrm{j}}\right) \mathrm{N}\) \(\overrightarrow{\mathrm{F}}=\mathrm{ma}=\left(6 \mathrm{t}+6 \mathrm{t}^2 \hat{\mathrm{j}}\right)\)…
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