What are the main concepts of electricity and magnetism?
What are the equations?

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What are the main equations and when do you know how to use them?

Well, I guess for your level, you have where V is the potential difference, I is the current, R is the net resistance and P is the power dissipated:

V = IR

P = IV

And deriving other equations from those two, we get:

P = I^2 R and P = \frac{V^2}{R}

For the definition of an ampere, the rate of flow of charge;

I = \frac{Q}{t}

To define the magnetic force, the force acting on a charge q moving at velocity v at perpendicular direction with the magnetic field B;

F = Bqv

The force on a current carrying wire carrying a current I and of length L, perpendicular to a magnetic field B;

F = BIL

Are you looking for more specific formulae?

Could someone explain the equation:

W=Pt=VIt=I[squared]Rt=V[squared]t/R.
Each part is equal to the other, I was just wondering if someone could more thoroughly explain this to me.

Thank's much!

[For electricity.]

You know the definition of power? It's the rate of doing work, or

P = \frac{W}{t}

Rearranging making Work the subject we get;

W = Pt

Now, in electricity, the power dissipated is given by: P = IV.

Replace in the equation for work:

W = IVt

Now, using Ohm's equation, V = IR, you first replace V by IR, giving:

W = I(IR)t = I^2Rt

or you replace the I by V/R, since I = V/R, to give:

W = (\frac{V}{R})Vt = \frac{V^2t}{R}

In other terms, if you have an appliance running at a certain voltage, or at certain current, and you know its resistance and the time it was working, you can find the electrical energy that it used, with that equation.