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Problem 44 Hard Difficulty

An object with mass $ m $ moves with position function $ \textbf{r}(t) = a \sin t \, \textbf{i} + b \cos t \, \textbf{j} + ct \textbf{k} $, $ 0 \leqslant t \leqslant \pi/2 $. Find the work done on the object during this time period.


Work done $$=\frac{m\left(b^{2}-a^{2}\right)}{2}$$


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Video Transcript

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