# # 3 Einstein’s Mass Energy Relation

Einstein, an absolute genius, has given a lot of groundbreaking theories and the one which completely changed our understanding was the Theory of Relativity. Being one of the most famous and fundamental scientific theories, it has a lot of revolutionary equations. In this article, we are going to talk about one such equation which is one of the most well-known equation in Physics. It is the Mass-Energy Relation.

Where,

- E is energy
- m is mass
- c is the speed of light

I am sure that most of you might be knowing this equation. Did you ever think that why is this equation so important and groundbreaking? Let us know.

Before Einstein giving this equation, the world used to think that energy and mass are two very different things. **Newtonian mechanics** told that object at rest has no energy but this equation opened our eyes and told that even an object at rest has an energy of **mc ^{2}**. This equation has drastically changed our understanding and told us that mass and energy are the same and are interconvertible.

So, the equation tells that you can create mass out of pure energy and you can get energy from the mass. When you add one joule of energy to a system, you are adding 1.11×10^{−17} kg of mass to that system. In daily life this is negligible but we see its consequences when we travel at speeds close to that of light. Einstein has given a mass velocity relation which tells the increase in mass with an increase in velocity.

Coming to the reverse process, the mass to energy conversion, 1 Kilogram of mass is equal to 9×10^{16} Joules which is really huge. If we could invent some method which can harness complete energy from mass then we wouldn’t need any other source for power. We know a process called Nuclear Fusion which can harness 0.7 times of this energy but sadly we don’t have the technology to do nuclear fusion on earth yet.

So, I hope that you got an essence of what this equation means and how did it change our understanding regarding mass and energy.

Read More: Famous Equations