I was very lucky to have some really great Elmer's over the years to help me along the way and teach me about Amateur Radio. I don't think a day goes by without me learning something new and that is what is so great about this hobby. I help my Wife Amy (WA8MY) teach Technician and General Class Theory at our local community center three times a year and it is nice being able to Elmer new Hams just as I was and still am for that matter.I hope some of the information below is helpful to all the Hams out there.

12 Formulas that every Ham should know

Ohm's law defines the relationship between Voltage, Current and Resistance E = I x R
where E is the electrical potential (voltage), measured in volts (V), I is the current, measured in Amperes (Amps/A), and R is the resistance, measured in Ohms (Ω).

Joule's law states that P = E x I
where P is Power, measured in Watts

The combination of Ohm's law and Joule's law gives us 12 formulas where 2 of the 4 variables are known. The wheel to the right is a handy tool and memory jogger. To use it, simply choose the quadrant corresponding to the variable you want to calculate, then select the segment corresponding to the variables that you know the value of.