Q) What is the resistance of a circuit that draws 4 amperes from a 12-volt source?
A) 3 ohms
NJ2X Notes:
Ohm's Law was discovered by Georg Simon Ohm and is worth committing to memory:
E = I * R
or by manipulating the terms algebraically:
I = E / R
or
R = E / I
In this example:
R = E / I
R = 12 volts / 4 amperes = 3 ohms
