Question
Find the work done in pulling and pushing a roller through $100m$ horizontally when a force of $1500N$ is acting along a chain making an angle of 60° with ground. Assume the floor to be smooth.

Answer

Here, forec F = 1500N and displacement, s = 100m $\theta=60^\circ$
$\therefore$ Work done, $\text{W}=\text{Fs}\cos\theta$
$=1500\times100\times\cos60^\circ$
$=1500\times100\times\frac{1}{2}$
$=75000\text{J}$
$=75\text{KJ}$

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