Here’s a quickie for those of you following along with the solar power class. Remember Ohm’s Law, which we’ve been discussing? Well, using the two formulae that I gave you earlier (E = I * R and P = I * E ), you can make 12 different formulas that will solve for any two out of three variables. Rather than break down the total chart, just look at this nice graphic depiction of the ways you can solve for each. Whether you prefer to use the original formulas or memorize all twelve of these, this will give you a better idea of the interrelation between the various components of electric circuitry.