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Magnetism

The direction of the magnetic force on a positive charge

Version 1 (right hand rule): point fingers of your right hand in the direction of $\vec v$ and curl them (through the smaller angle) toward $\vec B$. Your upright thumb shows the cross product $\vec v \times \vec B$ or the magnetic force $\vec F_B$. This force is perpendicular to the plane of $\vec v-\vec B$

Version 2 (right hand rule): point your fingers in the direction of $\vec B$ so the thumb points toward the velocity $\vec v$, the magnetic force on a positive charge is in the outward direction of your palm.

Note: the magnetic force on a negative charge is in opposite direction to that given right hand rule.