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

If Superman were to fly fast enough, his relativistic mass would be 13.7 million times his normal mass.

From National Geographic