<p>I need this explained in a lot of detail. As well as each variable explained:</p>
<p>E= k * Q/r^2</p>
<p>Think of what the electric field really is- it’s just a ratio of the force felt by a charge right? Let’s say E=F/q1. While this is useful if you know the magnetic field and the amount of charge, it is not useful in defining the electric field with respect to distance. What can we do in this case then? Well, we can relate electric force of attraction of two charges to distance using F=(k<em>q1</em>q2)/d^2, so why don’t we plug that into the first equation? That’s how E=kq/d^2 came about. Hopefully this helped.</p>