Work done by a force vec F = left( { - 6{x^3}hat{i}} right),N in displacing a particle from x

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5.Work, Energy, Power and Collision

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The work done by a force $\vec F = \left( { - 6{x^3}\hat i} \right)\,N$ in displacing a particle from $x = 4\,m$ to $x = -2\,m$ is ............... $\mathrm{J}$

A

$-240$

B

$360$

C

$420$

D

will depend upon the path

Solution

$\int {dW} = \int {\vec F\,d\vec s} = – \int\limits_4^{ – 2} {6{x^3}dx} $ $=360\,J$

Standard 11

Physics

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