• # question_answer A force $\vec{F}=6\hat{i}+2\hat{j}-3\hat{k}$acts on a particle and produces a displacement of $\vec{s}=2\hat{i}-3\hat{j}+x\hat{k}.$If the work done is zero, the value of $x$is: A) $-2$                            B) $\frac{1}{2}$             C)    6                     D)    2

$W=\vec{F}.\vec{s}=(6\hat{i}+2\hat{j}-3\hat{k}).(2\hat{i}-3\hat{j}+x\hat{k})=0$ or,$12-6-3x=0$$\Rightarrow x=2$ Hence, the correction option is (d).