angular momentum

American  

noun

Physics.

1. the product of the moment of inertia of a body about an axis and its angular velocity with respect to the same axis.

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angular momentum British  

noun

1. a property of a mass or system of masses turning about some fixed point; it is conserved in the absence of the action of external forces

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angular momentum Scientific  

/ ăng′gyə-lər /

1. A measure of the momentum of a body in rotational motion. The angular momentum of rigid bodies is conserved; thus, a spinning sphere will continue to spin unless acted on by an outside force. Changes in angular momentum are equivalent to torque. In classical mechanics, angular momentum is equal to the product of the angular velocity of the body and its moment of inertia around the axis of rotation. It is a vector quantity; the vector points up along the axis of counterclockwise rotation. In quantum mechanics, the angular momentum of a physical system is quantized and can only take on discrete values.

2. See also Planck's constant spin

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Etymology

Origin of angular momentum

First recorded in 1865–70

Example Sentences

See Examples For:

angular momentum

According to the researchers, the result acts as a direct quantum mechanical signature of angular momentum conservation inside solids.

From Science Daily ● May 24, 2026

Their famous experiment showed that magnetic and mechanical angular momentum are linked together.

From Science Daily ● May 24, 2026

In physics, quantities such as energy, momentum, and angular momentum are conserved, meaning they cannot disappear or be created from nothing.

From Science Daily ● May 24, 2026

This produced a flow of orbital angular momentum, which the team named the orbital Seebeck effect, drawing inspiration from the spin Seebeck effect that influences electron spin.

From Science Daily ● Apr. 19, 2026

Neutrinos, like protons, electrons and neutrons, carry an intrinsic angular momentum, or spin, while photons have no spin at all.

From "Cosmos" by Carl Sagan