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So far, we know that charge is a property of all matter, whether it be a positive, negative, or neutral overall charge. We also know that charge is responsible for all electrical and magnetic forces and interactions.
But what is the electric force?
How can a force be applied to an object without contact between the two objects? Or, in other words, how can we push something without physically pushing it?
We're already familiar with gravity, and how one mass can affect the other. If one mass is placed in the gravitational field of the other, there is a gravitational attraction between the two objects. Likewise, if an electric charge is placed in the electric field of another charge, their fields will affect the other particle.
If we want to make a model to represent the charge and its field we can represent the charge as a positive charge, and draw lines representing the field.
How can we determine regions of high and low field strength?
(insert diagram of 2 fields, one of high strength and one of lower strength)
If we look at the field lines, the greater number in an area (or the more dense the field lines are). The greater the strength of the field, relative to an area with lower field line density. This works qualitatively, what we do not know, is the quantity representing the field strength. We know an area of high density is stronger than an area of low density, but what we do not know is just how much stronger it is.
To take a look at some electric charge arrangements and their fields, please take a peek at this site from Lawrence Technical University. Can you find the areas of higher field strength?
Now that we know what an electric field is, and how to describe the force created by an electrical charge. What do you think would create a stronger electric field? More charge? Less Charge?
How do we know how much charge we have?
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