# The mass of the atom is due to the energy of strong force. So it is energy and not mass right?

1. Oct 3, 2014

### avito009

The mass of the nucleons (and, by extension, most of the visible universe) is caused by the energy stored up in the force field of the strong nuclear force. Please Explain this to me in layman's terms. I would appreciate the help. (I am being polite because phinds said so).

How does the energy of strong nuclear force get converted to mass inside the nucleous?

2. Oct 3, 2014

### mathman

Protons and neutrons are each made up of three (valence) quarks plus gluons and virtual quark-antiquark pairs. The masses of the valence quarks add up to a small fraction of the total mass of either nucleon. The rest of the masses comes from the rest of the stuff which can be described as energy.

3. Oct 3, 2014

### Staff: Mentor

It's not so much that it is "converted to mass" as that energy has mass, as given by Einstein's famous $E=mc^2$. For example, a charged electrical battery weighs slightly (very very slightly - it is a good exercise to calculate how much) more than the same battery when discharged.

The strong nuclear force is so strong over very short distances that the energy content of the nucleus accounts for a large fraction of the total mass of the nucleus.