A) \[14\,\hat{i}-38\hat{j}+16\,\hat{k}\]
B) \[4\,\hat{i}+4\hat{j}+6\,\hat{k}\]
C) \[14\,\hat{i}+38\hat{j}-16\,\hat{k}\]
D) \[-21\,\hat{i}+3\hat{j}+5\,\hat{k}\]
Correct Answer: C
Solution :
Torque \[\tau =\vec{F}\times \vec{r}\] \[=(-3\hat{i}+\hat{j}+5\hat{k})\times (7\hat{i}+3\hat{j}+\hat{k})\] or \[\vec{\tau }=\left| \begin{matrix} {\hat{i}} & {\hat{j}} & {\hat{k}} \\ -3 & 1 & 5 \\ 7 & 3 & 1 \\ \end{matrix} \right|\] \[=-14\hat{i}+38\hat{j}-16\hat{k}\]You need to login to perform this action.
You will be redirected in
3 sec