A particle acted on by constant forces 4i^+j^−3k^ and 3i^+j^−k^ is displaced from the point i^+2j^+3k^ to the point 5i^+4j^+k^. The total work done by the forces is:
Solutions · 1
Official solution
Resultant force F=(4i^+j^−3k^)+(3i^+j^−k^)=7i^+2j^−4k^
Displacement d=(5i^+4j^+k^)−(i^+2j^+3k^)=4i^+2j^−2k^
\[W=\vec F\cdot\vec d = 28+4+8=40\text{ units}\]