Torque on a uniform disk of mass \(2\text{ }\text{kg}\), radius \(1\text{ }\text{m}\), is given as \(\tau (t)=5{t}^{2}−8…

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\(\begin{aligned}& \rho=\vec{\tau} \cdot \vec{\omega} \\& \tau=l \alpha \\& I=\frac{M R^2}{2}=1 \\& \alpha=5 t^2-8 t \\& \omega=\frac{5}{3} t^3-4 t^2 \\& \text { At } t=1, \omega=\frac{5}{3}-4=-\frac{7}{3} \\& t(3)=5-8=-3 \\& \rho=\vec{\tau} \cdot \vec{\omega}=7 \mathrm{~W}\end{aligned}\)