In AP® Physics, angular momentum is the rotational equivalent of linear momentum. The magnitude of the angular momentum of a rigid system about a specific axis can be described by the equation:
Where:
= angular momentum, in
= rotational inertia, in
= angular velocity, in
Objects traveling in a straight line can possess both linear and angular momentum. The magnitude of this angular momentum depends on the particle's position relative to an axis of rotation. When a particle moves on a line relative to the axis, it will cause rotation and therefore has angular momentum. When a particle moves on a line that passes through the axis, it will not cause rotation and therefore has zero angular momentum.
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