Fleming's Left Hand Rule

If we place an open left hand with the palm up so that the fingers point to the direction of the current through the conductor and the induction lines of the magnetic field enter the palm, then the thumb will show the direction of the force exerted by the magnetic field on the conductor (as you can see in the picture).

or: "If the fingers show the direction of the current and the induction lines of the magnetic field enter the palm, then the thumb shows the direction of the force exerted by the external magnetic field on the current-carrying conductor.

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