right-hand rule

electromagnetism

Also known as: Fleming’s rule

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Last updated

June 17, 2026

Quick Summary

The right-hand rule is a mnemonic device used in electromagnetism to determine the direction of forces, fields, or currents. When dealing with a current-carrying wire, if you point the thumb of your right hand in the direction of the current, your fingers will curl in the direction of the magnetic field lines around the wire.12

In the context of the Lorentz force, which describes the force on a moving charged particle in a magnetic field, the right-hand rule helps determine the direction of this force. If your thumb points in the direction of the particle's velocity and your forefinger points in the direction of the magnetic field, your middle finger will indicate the direction of the resulting force. This rule is fundamental for understanding interactions between electricity and magnetism.342

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electromagnetism
Experimental and theoretical studies of electromagnetic phenomena
…was able to express the right-hand rule for the direction of the force on a current in a magnetic field. He also established experimentally and quantitatively the laws of magnetic force between electric currents. He suggested that internal electric currents are responsible for permanent magnets and for highly magnetizable materials…
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…was able to express the right-hand rule for the direction of the force on a current in a magnetic field. He also established experimentally and quantitatively the laws of magnetic force between electric currents. He suggested that internal electric currents are responsible for permanent magnets and for highly magnetizable materials…
Read More

magnetism
Lorentz force
…dF is given by the right-hand rule illustrated in Figure 6. As shown, the fingers are in the direction of B; the current (or in the case of a positive moving point charge, the velocity) is in the direction of the thumb, and the force is perpendicular to the palm.
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…dF is given by the right-hand rule illustrated in Figure 6. As shown, the fingers are in the direction of B; the current (or in the case of a positive moving point charge, the velocity) is in the direction of the thumb, and the force is perpendicular to the palm.
Read More