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Angular Momentum: Definition, Units, and Formula

The following article is on angular momentum. It includes the definition of angular momentum, its units, and the formula. It also discusses angular momentum examples.

To define momentum, certain things have to be kept in mind. Momentum is a property of an object that manifests as movement and its changes in a body in motion. Momentum is simply the product of the velocity and mass of a body of a particle. To define momentum as a vector quantity will be correct. Momentum has direction as well as magnitude and is related to the laws propagated by Newton. In physics, particularly Newtonian mechanics, momentum is also known as linear momentum. Angular momentum is a type of momentum in physics. Angular momentum talks about rotational bodies. 

Angular Momentum

Angular momentum meaning is a type of momentum. Here, the rotational movement is concerned with the body in rotation around an axis. It can be said that it is analogous to the rotation of the momentum. It is identified as a conserved quantity. There are certain features of angular momentum that make up the define momentum:

  • Angular momentum is constant in a closed system
  • Conservation acts as a limiting feature on the possible motions but is not completely deterministic
  • It is extensive
  • Rigid and continuous body and fluid display that the angular momentum is equal to its density
  • Angular momentum is not conserved when an outside torque is applied to it

Torque is associated with angular momentum and is defined simply as the changing rates in angular momentum over some time. In physics, particularly Newtonian mechanics, momentum is also known as linear momentum. Angular momentum is a type of momentum in physics. Angular momentum meaning talks about rotational bodies. The properties of frisbees and bullets showcase angular momentum in action. 

Define Momentum

Momentum is represented as (P) and its mathematical formula is P = mv, where m is mass and v is the velocity. Momentum is direction as well as the magnitude and is related to the laws propagated by Newton. To define momentum, certain things have to be kept in mind. Momentum is a property of an object that manifests as movement and its changes in a body in motion. To define momentum, the mass of a body or a particle and its velocity has to be calculated. 

Types of Angular Momentum

Angular momentum is of two types:

  • Orbital angular momentum- this defines the angular momentum of a body around a rotational center. It is expressed as L=Iw where I is momentum inertia, L is the angular momentum and w is angular speed. Here I = r²m (m is point mass) and w = r*v/r² (r is position vector and v is linear velocity). 
  • Spin angular momentum- This is the angular momentum around the body’s center of mass. 

The formula of Angular Momentum is L=Iw (I is momentum inertia, L is the angular momentum and w is angular speed). The unit of angular momentum is kg m² s-¹and its dimensions are ML²T-¹. 

Example of Angular Momentum

An example of angular momentum is that neutron stars possess very high rates of rotation and it is due to angular momentum. Another example is the spirals evident in hurricanes. 

Conclusion

Angular momentum is also evident in the operations of bikes and motorcycles. The angular momentum increases with the increase in the mass of a body and the distance between it and its rotational center. Angular momentum involves displacement and mass. It also contains shape and position which is different from linear momentum. In physics, a moment is defined as the multiplying effect of momentum along the length in proportion.

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What is angular momentum?

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What is torque?

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What is momentum?

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What are the types of angular momentum?

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