Bilingual edition: English is preserved and Chinese follows each unit. Terminology uses the confirmed v20260916 glossary; automated semantic review remains traceable.
中英双语版:英文原文完整保留,中文紧随对应单元;术语采用 v20260916 确认表,自动语义审校结果可追溯。

Angular Momentum of a Particle

粒子的角动量

The angular momentum of a particle of mass m with respect to a chosen origin is given by

一个质量为m的质点相对于所选原点的角动量由
L = mvr sin θ

or more formally by the vector product

或更正式地说,通过矢量积
L = r x p

The direction is given by the right hand rule which would give L the direction out of the diagram. For an orbit, angular momentum is conserved, and this leads to one of Kepler's laws. For a circular orbit, L becomes

方向由右手法则给出,这会使L指向图外。对于轨道,角动量是守恒的,这导致了开普勒定律之一。对于圆轨道,L变为
L = mvr
L = mvr sin θ L = r × p L = mvr
Index

Angular momentum of rigid body
刚体的角动量索引
 
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HyperPhysics ***** 力学 ***** 转动运动
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Angular Momentum

角动量

The angular momentum of a rigid object is defined as the product of the moment of inertia and the angular velocity. It is analogous to linear momentum and is subject to the fundamental constraints of the conservation of angular momentum principle if there is no external torque on the object. Angular momentum is a vector quantity. It is derivable from the expression for the angular momentum of a particle

刚体的角动量定义为转动惯量与角速度的乘积。它类似于线动量,并且在物体上没有外力矩作用时,它遵循角动量守恒原理。角动量是一个矢量量。它可以从质点的角动量表达式导出。

Comparison of linear and angular momentum
线动量与角动量的比较
Index

Moment of inertia concepts
索引 转动惯量概念
 
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Angular and Linear Momentum

角动量和线动量

Angular momentum and linear momentum are examples of the parallels between linear and rotational motion. They have the same form and are subject to the fundamental constraints of conservation laws, the conservation of momentum and the conservation of angular momentum .

角动量和线动量是线运动和旋转运动之间相似性的例子。它们具有相同的表达形式,并受动量守恒和角动量守恒等基本约束的制约。
Index

Moment of inertia concepts
索引 转动惯量概念
 
HyperPhysics***** Mechanics *****Rotational motion
HyperPhysics ***** 力学 ***** 转动运动
R Nave
Go Back
返回