73. According to the figure, a body of mass $100\,\text{g}$ is launched from a height of $4\,\text{m}$ above an inclined surface with velocity $4\,\dfrac{\text{m}}{\text{s}}$ and lands on the inclined surface, then slides down with velocity $10\,\dfrac{\text{m}}{\text{s}}$. How many joules of work is done by the resistive forces on the body? $\left(g = 10\,\dfrac{\text{m}}{\text{s}^2}\right)$ [Figure: Inclined plane with angle $\alpha$, showing projectile path.]
[(1)] $-2.1$
[(2)] $-2.4$
[(3)] $-4.2$
[(4)] $-5.8$
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\textbf{73.} According to the figure, a body of mass $100\,\text{g}$ is launched from a height of $4\,\text{m}$ above an inclined surface with velocity $4\,\dfrac{\text{m}}{\text{s}}$ and lands on the inclined surface, then slides down with velocity $10\,\dfrac{\text{m}}{\text{s}}$. How many joules of work is done by the resistive forces on the body? $\left(g = 10\,\dfrac{\text{m}}{\text{s}^2}\right)$
\textit{[Figure: Inclined plane with angle $\alpha$, showing projectile path.]}
\begin{itemize}
\item[(1)] $-2.1$
\item[(2)] $-2.4$
\item[(3)] $-4.2$
\item[(4)] $-5.8$
\end{itemize}
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