Electric Field versus Gravitational Field.
The gravitational field is a always attractive but the electric field has two different forms. While the gravitational field has all objects pulling each other, the electric field can push or pull objects.

Electric Field

The Electric Field is yet another way which two objects are able to interact with each other without any physical contact (gravity and electrostatic being two others). Michael Faraday developed the best method of visualizing the Electric Field, which we will currently be discussing.

The Electric Field exists around all charged objects. Michael Faraday's method of diagramming the electric field is to put a small positive test charge and whichever way it moves, that is the way the electric field at that place is in space is pointing.

So if you have a positive charge next to a proton it would move away (electric field lines come out of protons and other positive objects), but if you had an electron, a positive charge would move towards it (electric field lines move into electrons and other negatively charge particles).

The Electric Field is actually very easy mathematically, especially after you know the Coulomb's Law. Think of Coulomb's Law, F=k * |q1| * |q2| / (r)^2, if one of the charges got really really small, or infinitely small then it would be equivalent to a "small positive test charge." And you would get a formula for the electric field.

E=k * q / r^2

Typically the electric field is drawn as arrows pointing out of protons and in to electrons, with the density of the arrows being a marker or how strong the electric field is at any point. So a particle with 4 lines coming out of it would be positive and is half as strong as a particle with 8 lines coming out of it. Electric field lines never cross, if two lines did exist in the same position then they would just be vectored together to produce one line.

Field lines aren't measured with any particular unit but only repectively to each other...

In reality electrons and protons aren't really pushing off each other all the time but are rather creating a field around themselves called the electric field which other charges react to.

This interpretation was discovered when experimentation revealed that there was a delay between the reactions of charged objects. This is a very simple experiment which you can do at home to see for yourself.

If you get two charged objects, like a balloon and a comb charged by static electricity, you can put them together.You can watch one spin while you move the other one. But when one object is moved the second object doesn't start to move immediatly, it takes a couple seconds for the charges to interact.

One more time but this time simpler: Electrons and protons aren't physically interacting but instead are changing the space around them so that other charged particles are affected.

Analogy Time

Imagine for a second that you are in a pool of water and you splash your friend. He doesn't immediately jump backwards because the water hasn't hit him yet. It takes time before he reacts and jumps away from you.

Then an adult picks you up and puts you in a different spot because he doesn't want you splashing him. As soon as you are dropped in the water you start splashing your friend from another direction but again it takes a couple of moments before your friend feels the water and jumps back.

Now imagine that you are placed in to a pool and as soon as you touch the water you start spinning. And since you get good at spinning you can create a whirlpool. It takes time to create a big enough whirlpool to start sucking your friend towards you. This is the way atoms affect each other. They don't actually push and shove each other but they change what is around them and to affect other charged particles.

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