Overall, Maxwell’s four equations describe the fundamentals of electricity and magnetism. However, one look at these mathematical equations can make a high school student run screaming from the room, so we’re not going to dive into the sophisticated mathematics of the equations themselves, but rather what they really tell us about the relationships between the electric and magnetic fields.

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Gravitational forces, magnetic forces, and electric forces are all action-at-a-distance forces (sometimes called field forces), meaning objects can interact even they are not touching each other.  The Earth and a ball are attracted to each other, even when the ball is tossed high up in the air. Two magnets can push against each other even when they are not touching. Same thing with two electrons: the negative charge on the electrons create a repulsive force that pushes on each electron.

A way to picture a force field is to imagine an invisible bubble that surrounds a gizmo. If some other object enters that bubble, that object will be pushed or pulled by an invisible force that is caused by the gizmo. That’s pretty bizarre to think about isn’t it?

Well,  not really. If you’ve ever been around a baby, you know that you can detect a diaper change without even peeking in there. The baby created a stinky field. It’s an invisible area that you can detect around the baby which increases in stinky-ness the closer to the baby you get. On the other hand, if you can imagine someone making your favorite meal and you walk into the house after a hard day, you enter into a wonderfully aromatic house filled with your favorite smells, you’re entering another field that you can detect, and the closer you get to the stove, the more intense the field becomes.

Click here to go to next lesson on Electric Field Lines.

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