The force of electric charges on each other is computed by Coulomb's Law. By using Coulomb's Law on each pair of charged particles and vectoring the resulting forces the direction of any particle can be found.. Mouthful isn't it?

OK, OK, you see it right? But do you understand it? The Qs are the strength of the charges. And the R is the space between the two particles (as measured from the center of the atoms). The K is a scalar quantity. k = 8.9875x10⁹

Here is a quick chart of all the charges or these atomic particles.

Food for thought - look closely at these numbers. What exactly do they mean? Notice how small the electron is compared to the proton, yet they have the same charge. Scientists are still not sure how or why this works, what exactly gives these things charges and why. It's just another mystery of the universe.

Advanced Theory - Some scientists believe that the universe used to be completely neutral and made only of neutrons, like way back in the moment after the big bang. But since a neutron is inherently unstable when by itself, they think that the neutrons would split up and turn in to a proton and an electron sets producing hydrogen atoms.

When you look around the universe many things appear to validate this theory. Hydrogen is by far the most common element in the universe and can be found everywhere.

Now look again at that formula The force between the two electrons is directly proportional to the charge of the two objects being measured. If you have higher charged atoms, then the force is greater. But the force is inversely proportional to the distance between the two objects.

Think of it in this way. You have two people standing next to each other. They push each other and they both go flying backward. If you make either of the people bigger (make the charges stronger) then they can push each other harder. But if they are farther away from each other then they can't get enough leverage and are not able to push each other as hard (think about trying to push someone who is just out of arm's reach so only your fingertips can touch them). That is the relationship two electrons have on each other or two protons have on each other.

But something different happens when you have a proton and an electron next to each other. It is the same formula but this time they pull each other as close as they can. Imagine you have someone at an arm's length from you and you are trying to pull them closer to you. As they get closer you can wrap your arms around them and pull them more easily because you are using both arms, This is the relationship that an electron and a proton have. Once again if you are bigger (you have a stronger charge) then it is easier to pull the other person (particle) to you.

Remember this is an invisible force. It doesn't need any physical contact to go straight through space (not air! - remember air doesn't exist at this level) and moves those atoms.

When you have two opposite and equally charged particles close to each other and another further away, what net force does the third particle feel?

attract, repel, none

answer - none. The third charge is being affected by the net charge of the two opposite charges so it is not feeling any force. However if you were to bring the third object closer it would start to attract to one and repel from the other. While it is doing this it would eventually get closer and closer to the opposite charge while further from the same charge.