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How can the right-hand rule determine the magnetic field direction around a current loop?

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Diagram showing a circular loop of wire with an electric current, surrounded by curved blue lines representing magnetic field lines that loop around the wire and pass through its center. — magnetism Some lines of the magnetic field B (blue) for an electric current I (gold) in a loop.

To determine the direction of the magnetic field around a current loop using the right-hand rule, you can use the following method:

If you curl the fingers of your right hand and hold them in the direction of the electric current flowing through the loop, your extended thumb will point in the direction of the magnetic dipole moment ( $𝐦$ ) of the loop. This direction is perpendicular to the plane of the loop and corresponds to the direction of the magnetic field ( $𝐁$ ) inside the loop.1

For example, if the current flows in a clockwise direction when viewed from above, the magnetic dipole moment—and thus the magnetic field inside the loop—points downward. Conversely, if the current flows counterclockwise, the magnetic field inside the loop points upward. This rule is a practical application of the principles governing the magnetic field of steady currents, which are fundamentally produced by moving charges.12