1. Choose a closed loop in the circuit. 2. Assign a direction to traverse the loop. 3. Sum the voltage changes around the loop, following sign conventions. 4. Set the sum equal to zero and solve for unknowns.

If traversing the resistor in the direction of current flow, the voltage change is negative (voltage drop). If traversing against the current, the voltage change is positive.

If traversing from the negative to the positive terminal, the voltage change is positive (voltage gain). If traversing from positive to negative, the voltage change is negative.

Draw a clear circuit diagram and label all known and unknown values, including voltage sources and resistances.

Double-check your signs for voltage gains and drops, and ensure that your final answer makes physical sense within the context of the circuit.

The sum of all voltage changes around any closed loop in a circuit must equal zero: $\sum \Delta V = 0$.

$\Delta U_{E} = q \Delta V$, where $\Delta U_{E}$ is the change in electric potential energy, $q$ is the charge, and $\Delta V$ is the change in electric potential (voltage).

The sum of all voltage changes (potential differences) as you go around a closed loop in a circuit is zero.

An increase in electric potential, typically provided by a battery or other voltage source.

A decrease in electric potential, typically occurring across a resistor due to energy dissipation.

The sum of all voltage changes around any closed loop in a circuit must equal zero.

The energy a charge possesses due to its position in an electric field.

The difference in electric potential between two points; also known as voltage.

The decrease in electric potential across a circuit element, such as a resistor.

The increase in electric potential provided by a source, such as a battery.