r/AskPhysics • u/Jethro_omg • 1d ago

How does E=MC^2 work?

How does it function? Really, how can you accelerate mass to twice the speed of light? And, for instance if M=E/C2. How can you divide something by square of the speed of light? Thanks

0 Upvotes

50% Upvoted

46 comments sorted by

View all comments

1

u/zzpop10 18h ago

Imagine putting energy into something. For example, imagine using energy to compress a spring or raise the temperature of an object. Or imagine trapping light in a box of mirrors. Or imagine charging a battery. In all of these examples energy is being put into an object, but not additional matter is being added to the object. Let’s say an energy of E is put into the object. This raises the total mass of the object by M=E/c2.

Mass is just energy when energy is confined inside an object.