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Physics

Mass Increase (Relativistic Mass)

Quick fact

A particle accelerated to 99.9999% of light speed in the Large Hadron Collider has a relativistic mass more than 7,000 times its rest mass.

Why this is interesting

Imagine pushing a sled: the harder you push, the faster it goes. But what if, as it gained speed, it also became heavier—so heavy that no amount of pushing could make it reach a certain speed?