relativistic mass

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.

relativistic mass

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

Example Sentences

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

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