# Tag Info

2

There is no particular reason why one should be of such a sign and the other of the other. The choice is mostly historical and the opposite choice (positive charge for the electron and negative for the proton) would work as well with just some slight sign changes in the equations. The only important part is that their charge be opposites.

-1

Protons are not an elementary particle, whilst electrons are. Protons are made up of Quarks, electrons aren't made up of difference constituent parts; they're just electrons. I'll leave it to you to look up the constituent parts of protons; they have individual charges within themselves. The actual reason that one is positive and one is negative is slightly ...

3

In answer to your question So, what is the anti-particle for proton? The following visual guide from the blog article Why Making Neutral Antimatter is Such A Big Deal! is helpful in this regard:

2

It's called the antiproton. You can literally google "proton antiparticle".

6

Let's consider two separate things: The mass (i.e. rest mass) of anything doesn't depend on its relative motion to an observer (i.e. is Lorentz invariant). For a proton, $m_p\simeq 1\,\text{GeV}/c^2$. The energy (occasionally egregiously called mass or relativistic mass in old-fashioned sources) of an object isn't Lorentz invariant. In the future, the LHC ...

10

You say: Now, when we talk about energetically favourably bound systems, they have a total mass-energy less than the sum of the mass-energies of the constituent entities. and this is perfectly true. For example if we consider a hydrogen atom then its mass is 13.6ev less than the mass of a proton and electron separated to infinity - 13.6eV is the ...

4

This happens because of a property of the strong force, called Asymptotic Freedom. This causes the interaction between quarks to get asymptotically weaker as the distance between them decreases. This is the reason why quarks are always found in a bound state and are not freely available in nature. The strong force confines quarks to a region where they ...

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