MCQ
A force of $-F$$\hat k$ acts on $O$, the origin of the coordinate system. The torque about the point $(1, -1)$ is
- A$-F$($\hat i$ - $\hat j$)
- B$F$($\hat i$ - $\hat j$)
- ✓$F$($\hat i$ + $\hat j$)
- D$-F$($\hat i$ + $\hat j$)
✓
Answer
Correct option: C.
$F$($\hat i$ + $\hat j$)
c
$\begin{array}{l}
Torque\,\overline \tau = \,\overline r \times \overline F = \left( {\hat i - \hat j} \right) \times \left( { - F\hat k} \right)\\
= F\left( {\hat i + \hat j} \right)
\end{array}$
$\begin{array}{l}
Torque\,\overline \tau = \,\overline r \times \overline F = \left( {\hat i - \hat j} \right) \times \left( { - F\hat k} \right)\\
= F\left( {\hat i + \hat j} \right)
\end{array}$
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