The figure shows three forces applied to a tr | vedclass

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(A) The displacement vector is $\vec{s} = -3\hat{i}\, m$.The forces acting on the trunk are:$\vec{F}_1 = -5\hat{i}\, N$$\vec{F}_2 = 9\cos(60^\circ)\ha

Vedclass · Accepted Answer

$1.50$

Vedclass · Answer

(A) The displacement vector is $\vec{s} = -3\hat{i}\, m$.The forces acting on the trunk are:$\vec{F}_1 = -5\hat{i}\, N$$\vec{F}_2 = 9\cos(60^\circ)\hat{i} + 9\sin(60^\circ)\hat{j} = 4.5\hat{i} + 4.5\sqrt{3}\hat{j}\, N$$\vec{F}_3 = -3\hat{j}\, N$The net force $\vec{F}_{net}$ is:$\vec{F}_{net} = \vec{F}_1 + \vec{F}_2 + \vec{F}_3 = (-5 + 4.5)\hat{i} + (4.5\sqrt{3} - 3)\hat{j} = -0.5\hat{i} + (4.5\sqrt{3} - 3)\hat{j}\, N$The net work done $W$ is the dot product of the net force and displacement:$W = \vec{F}_{net} \cdot \vec{s} = (-0.5\hat{i} + (4.5\sqrt{3} - 3)\hat{j}) \cdot (-3\hat{i})$$W = (-0.5 	imes -3) + (0) = 1.5\, J$.

The figure shows three forces applied to a trunk that moves leftward by $3\, m$ over a smooth floor. The force magnitudes are $F_1 = 5\, N$,$F_2 = 9\, N$,and $F_3 = 3\, N$. The net work done on the trunk by the three forces is ............... $J$.

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