Torque is the cross product of force and distance. Almost all the resources I find online have the formula as $\vec\tau=\vec d\times \vec F$, yet my professor (and I've seen some other sources do this) insists on using $\vec\tau=\vec F\times \vec d$. From what I've learned, swapping the two vectors in the cross product gives a vector of same magnitude but in the opposite direction. This gives a different answer, so which one is supposed to be used?
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$\begingroup$ You may believe Wikipedia - en.wikipedia.org/wiki/Torque in this regard. Further, cite at least one resource which says that $\vec \tau=\vec F\times \vec d$ instead of $\vec \tau=\vec d\times \vec F$ $\endgroup$– VishnuCommented Mar 3, 2020 at 8:23
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$\begingroup$ Does your professor also define angular momentum as $\vec{L}=\vec{p}\times\vec{d}$ rather than $\vec{L}=\vec{d}\times\vec{p}$? If so, it’s consistent but rather eccentric. $\endgroup$– G. SmithCommented Mar 3, 2020 at 17:23
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1 Answer
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$\vec \tau=\vec r \times \vec F$ is consistent with the right-hand grip / right-hand corkscrew rule.
