A) \[4\hat{i}-4\hat{j}+6\hat{k}\]
B) \[14\hat{i}+14\hat{j}-6\hat{k}\]
C) \[-21\hat{i}+\hat{j}-4\hat{k}\]
D) \[14\hat{j}-38\hat{j}+16\hat{k}\]
Correct Answer: D
Solution :
Using the relation, \[\overrightarrow{\tau }=\overrightarrow{r}\times \overrightarrow{F}=\left| \begin{matrix} {\hat{i}} & {\hat{j}} & {\hat{k}} \\ 7 & 3 & 1 \\ -3 & 1 & 5 \\ \end{matrix} \right|\] \[=\hat{i}(15-1)-\hat{j}(35+3)+\hat{k}(7+9)\] \[=14i-38j+16\hat{k}\]You need to login to perform this action.
You will be redirected in
3 sec