Potential drop

Definition

Potential drop is the decrease in electric potential energy per unit charge as a current flows through a component or resistor in a circuit. It is measured in volts (V).

5 Must Know Facts For Your Next Test

1. Potential drop across a resistor can be calculated using Ohm's Law: $V = IR$, where $I$ is the current and $R$ is the resistance.
2. In a series circuit, the total potential drop equals the electromotive force (EMF) of the source.
3. Kirchhoff's Voltage Law states that the sum of all potential drops around any closed loop in a circuit must equal zero.
4. The potential drop across each component in parallel circuits is the same and equal to the supply voltage.
5. Potential drop indicates how much energy per unit charge is converted into other forms like heat.

Review Questions

• What equation would you use to calculate the potential drop across a resistor?
• How does Kirchhoff's Voltage Law apply to potential drops in a closed loop?
• What is the relationship between potential drops in series and parallel circuits?

Related terms

Ohm's Law:

$V = IR$, where $V$ is voltage, $I$ is current, and $R$ is resistance.

Electromotive Force (EMF):

The energy provided by a power source per unit charge. Measured in volts (V).

Kirchhoff's Voltage Law: The principle that the sum of all electrical potential differences around any closed circuit loop must be zero.