What is spin (angular momentum)? - Definition from WhatIs.com

Definition

spin (angular momentum)

Part of the Computing fundamentals glossary:

In physics, spin is the velocity of rotation of something around a particular axis. Spin is sometimes called angular momentum, which is defined as:

(mass) x (velocity) x (radius), where radius is the distance from the spinning object to the axis.

Conservation of angular momentum, one of the fundamental laws of physics, observes that the angular rotation of a spinning object remains constant unless acted upon by external torque.

The underlying principle can be illustrated by the spin of a figure skater with outflung arms, considering the spinning object the skater's hands and the body the axis. Velocity is inversely proportional to the radius, increasing if the radius becomes smaller and decreasing if it becomes larger. Similarly, the distance of the skater's hands from his body controls the speed of the spin: As the skater brings the arms in closer to the body (at a smaller angle relative to the body), the speed of the spin increases and as he moves them farther out (at a greater angle relative to the body), the speed of the spin decreases.

Spin of subatomic particles is measured in multiples of a unit called the Dirac h, or h-bar.

Gyroscopes exploit the conservation of angular momentum to stabilize, guide or measure rotational movement in many types of systems. Wheels on a bicycle, for example, act as gyroscopes as they spin up to speed, making it easier to stay upright and harder to upset momentum. 

Khan Academy explores angular momentum:

In public relations and journalism, spin is the selective assembly of fact and nuance to support a particular view of a story.

This was last updated in March 2016
Posted by: Margaret Rouse

Related Terms

Definitions

  • DOS

    - DOS (Disk Operating System) can refer to a computer operating system that is loaded from a disk drive or to an operating system based on Microsoft Disk Operating System (MS-DOS). (SearchSecurity.com)

  • supercomputer

    - The first commercially successful supercomputer, the CDC (Control Data Corporation) 6600 was designed by Seymour Cray. Released in 1964, the CDC 6600 had a single CPU and cost $8 million — the equi... (WhatIs.com)

  • URL shortening

    - A URL shortener is a service that translates long URLs into abbreviated alternatives. (WhatIs.com)

Glossaries

  • Computing fundamentals

    - Terms related to computer fundamentals, including computer hardware definitions and words and phrases about software, operating systems, peripherals and troubleshooting.

  • Internet applications

    - This WhatIs.com glossary contains terms related to Internet applications, including definitions about Software as a Service (SaaS) delivery models and words and phrases about web sites, e-commerce ...

Ask a Question About spin (angular momentum)Powered by ITKnowledgeExchange.com

Get answers from your peers on your most technical challenges

Tech TalkComment

Share
Comments

    Results

    Contribute to the conversation

    All fields are required. Comments will appear at the bottom of the article.