Potential Difference and Electric Potential

The energy of a particle in a electric field is a conservative force, which means that it depends of it's on its start and end position to determine the work done. Because the force on a charged particle is equal to qE and work = Fd

W=FD=qEd

Or the work done on an electron is proportional to the strength of the charge, the strength of the field and the distance it is moved. Since work, by definition is equal to negative potential energy(PE)

deltaPE= -QED (only valid for uniform electric fields)

This chapter has a lot of very similar terms and I'm going to list them really quickly to get them straight.

Work(W) FD or QED work done to move a particle in a field
  think of work as the amount of energy you need to push two like charged particles together.
Potential Energy(PE) -W or -QED or deltaPE potential energy is the amount of energy a particle can release in an electric field
  the amount of energy two like charge release when they are pushing off each other.
Potential Difference(V) deltaV or -Ed voltage is a quantity to determine PE without a charge involved.

 

 Potential Difference is strength of the electric field at a point between charges.

Potential Energy

Now this is a rather delicate subject to understand, particles lose and gain electricity in much the same way an object rolling down a hill might. Imagine a ball on the top of the hill. Atat the top it has potential energy and as it rolls to the bottom it loses its energy.

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How exactly do rolling balls have anything to do with charged particles? Imagine for a second that the hill is actually an electric field (with the positive end at the top of the hill and the negative end at the bottom of the hill). The ball (a positive particle) sits on the hill and has potential energy but loses it as it rolls down the hill (goes with the electric field).

Why does this happen? Lets say you have a positive charge on the left and a negative charge on the right. Electric field lines would be moving from the left to the right. If you put a positive charge near the positive charge (the top of the hill) it will try and get away from the positive charge and to the negative charge. So at the point near the positive charge it has the ability to move in the electric field (or roll down the hill). As it moves away from the positive charge it loses its potential energy. A positive charge loses PE as it moves along with the electric field.

The same thing happens with negative charges only opposite. Instead they are repelled from the negative charge and attracted to the positive charge. So they have PE when they are close to the negative charges and lose PE as they near the positive charges. A negative charge loses PE as it moves against the electric field.

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