Physics - W.E.P. Question with Solution | TestHub

Using the formula for work done $W=\overrightarrow{\mathbf{F}}\cdot \overrightarrow{\mathbf{r}}=\overrightarrow{\mathbf{F}}\cdot \left(\overrightarrow{{\mathbf{r}}_2}-\overrightarrow{{\mathbf{r}}_1}\right)$ $\begin{array}{r}W=(4\hat{\mathbf{i}}+\hat{\mathbf{j}}+3\hat{\mathbf{k}})\cdot (14\hat{\mathbf{i}}+13\hat{\mathbf{j}}+9\hat{\mathbf{k}})-3\hat{\mathbf{i}}-2\hat{\mathbf{j}}+6\hat{\mathbf{k}})\end{array}$ $\begin{array}{rl}& W=(4\hat{\mathbf{i}}+\hat{\mathbf{j}}+3\hat{\mathbf{k}})\cdot (11\hat{\mathbf{i}}+11\hat{\mathbf{j}}+15\hat{\mathbf{k}})\\ & W=44+11+45=100\text{ joule }\end{array}$