JEE Mains · Physics · STD 11 - 5. work,energy,power and collision
An object of mass 1000 g experiences a time dependent force \(\vec{F}=\left(2 t \hat{i}+3 t^2 \hat{j}\right) N\). The power generated by the force at time \(t\) is :
- A \(\left(2 t^2+3 t^3\right) W\)
- B \(\left(2 t^2+18 t^3\right) W\)
- C \(\left(3 t^3+5 t^5\right) W\)
- D \(\left(2 t^3+3 t^5\right) W\)
Answer & Solution
Correct Answer
(D) \(\left(2 t^3+3 t^5\right) W\)
Step-by-step Solution
Detailed explanation
\begin{aligned} & \overrightarrow{\mathrm{F}}=(2 t \hat{\mathrm{i}}+3 \mathrm{t} \hat{\mathrm{j}}) \mathrm{N} \\ & \mathrm{m}=1000 \mathrm{gm}=1 \mathrm{~kg} \\ & \overrightarrow{\mathrm{~F}}=m \overrightarrow{\mathrm{a}}, \overrightarrow{\mathrm{a}}=2 \mathrm{t}…
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