How to understand the components of angular momentum along the coordinate axis?

You should have learned the cross product of vectors ( ), angular momentum and moment are both vector cross products, angular momentum l=r p (r is a space vector, is a vector, p is momentum, is also a vector), then, r on the xyz axis is xi, yj, z k, p on the xyz axis is p(x)i, p(y)j, p(z)k, (i,j,k are the unit vectors in the x,y,z directions), so.

l = （ xi+yj+z k ）×p（x）i + p（y）j + p（z）k 】

yp（z）-zp（y）】i + zp（x）-xp（z）】j + xp（y）-yp（x）】k

So the component of l on the xyz axis is .

l（x）=yp（z）-zp（y）；

l（y）=zp（x）-xp（z）；

l（z）=xp（y）-yp（x）；

Moment ( m=r f, m is the moment, r is the space vector, f is the force, they are all vectors) is the same calculation, you just know the cross product of the vector can be found, very simple, if there is anything you don't understand, just ask me.

Agree with the upstairs, but it's more convenient to express the determinant with the help of vector cross products.

Multiply with a fork, determinant.

This means r x p=

i j k |

x y z |

px py pz|

In a planar polar coordinate system, only the lateral component of momentum contributes to angular momentum. In other words, angular momentum is a physical quantity that describes the change of the direction of motion of a particle relative to a reference point or the rotational characteristics of an object, and it is mainly a physical quantity introduced to study the curvilinear motion such as elliptical motion and circular motion of a particle and the rotation of an object.

In physics, angular momentum (angular momentum) originates and objects are associated with displacement and momentum.

Angular Momentum Angular momentum is a system consisting of the interaction of two particles, in addition to the momentum another reference point o The momentum of the particle or the conservation of momentum moment is called an angle. It is defined as:

In a planar polar coordinate system, only the momentum of the angular momentum of the transverse components contributes. In other words, the description of the angular momentum of the particle with respect to the reference point or the physical quantity of the object, which is characterized by the movement of the direction of rotation, is mainly for the study of the problem, the elliptical and circular curves of the particle motion and rotational motion of the object and the introduction of a physical quantity.