Browse Definitions :
Definition

electron rest mass

The electron rest mass, symbolized m e , is the mass of an electron as measured when its speed is zero relative to an observer. The electron has extremely small mass  -- it's almost 2000 times less massive than the proton -- at approximately 9.10956 x 10 -31 kilogram (kg) or 9.10956 x 10 -28 gram (g). Every known electron at rest has the same mass as every other known electron at rest.

When an electron is accelerated to high speed, its mass increases because of relativistic effects. This increase is not significant until the speed of the particle, relative to the observer, becomes an appreciable fraction of the speed of light . If v is the speed of an electron in meters per second (m/s) and c is the speed of light (approximately 2.99792 x 10 8 m/s), then the mass of an electron in motion, m e* , is

m e* = m e / (1 - v 2 /c 2 ) 1/2 = 9.10956 x 10 -31 / (1 - v 2 /c 2 ) 1/2 kg

The exponent refers to the square root .

The relativistic mass increase of high-speed electrons is significant in real-world scenarios, because it increases the effects of the electrons on objects they strike. High-speed electrons are known as beta particle s.

Also see Table of Physical Units and Constants.

This was last updated in September 2009

SearchCompliance

  • information governance

    Information governance is a holistic approach to managing corporate information by implementing processes, roles, controls and ...

  • enterprise document management (EDM)

    Enterprise document management (EDM) is a strategy for overseeing an organization's paper and electronic documents so they can be...

  • risk assessment

    Risk assessment is the identification of hazards that could negatively impact an organization's ability to conduct business.

SearchSecurity

  • honeypot (computing)

    A honeypot is a network-attached system set up as a decoy to lure cyber attackers and detect, deflect and study hacking attempts ...

  • spam trap

    A spam trap is an email address that is used to identify and monitor spam email.

  • cracker

    A cracker is someone who breaks into someone else's computer system, often on a network; bypasses passwords or licenses in ...

SearchHealthIT

SearchDisasterRecovery

  • risk mitigation

    Risk mitigation is a strategy to prepare for and lessen the effects of threats faced by a business.

  • call tree

    A call tree is a layered hierarchical communication model that is used to notify specific individuals of an event and coordinate ...

  • Disaster Recovery as a Service (DRaaS)

    Disaster recovery as a service (DRaaS) is the replication and hosting of physical or virtual servers by a third party to provide ...

SearchStorage

  • storage virtualization

    Storage virtualization is the pooling of physical storage from multiple storage devices into what appears to be a single storage ...

  • erasure coding

    Erasure coding (EC) is a method of data protection in which data is broken into fragments, expanded and encoded with redundant ...

  • continuous data protection

    Continuous data protection (CDP), also known as continuous backup, is a backup and recovery storage system in which all the data ...

Close