Circuit Theory

Ohm’s Law

Ohm determined experimentally that current in a resistive circuit is directly
proportional to its applied voltage and inversely proportional to its resistance.
In equation form, Ohm’s law states
I =E/R [amps, A]
where
E is the voltage in volts,
R is the resistance in ohms,
I is the current in amperes

Kirchhoff’s Voltage Law

Next to Ohm’s law, one of the most important laws of electricity is Kirchhoff’s
voltage law (KVL) which states the following:
The summation of voltage rises and voltage drops around a closed loop
is equal to zero.