relativistic mass

American  

noun

Physics.

1. the mass of a body in motion relative to the observer: it is equal to the rest mass multiplied by a factor that is greater than 1 and that increases as the magnitude of the velocity increases.

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relativistic mass Scientific  

/ rĕl′ə-tə-vĭs′tĭk /

1. In Special and General Relativity, the observed mass of an object moving with respect to the observer. The relativistic mass is a function of the rest mass and the velocity of the object.

2. Compare rest mass

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Example Sentences

When Grebe adds a time-related dimension, velocity in the form of relativistic mass, the results match the known values for the particle masses.

From Time Magazine Archive