Ohm's law is the scientific relationship between current (Amperes, A) and voltage (volts, V), plus power (watts, W):
U = R x I (with U in Volt, R in Ohm, I in Ampere)
I = U / R (with U in Volt, R in Ohm, I in Ampere)
P = U x I (with P in Watt, U in Volt, I in Ampere)
P = U x U / R (with P in Watt, U in Volt, R in Ohm)
P = R x I x I (with P in Watt, R in Ohm, I in Ampere)
To your calculators :-)
