Potential difference

Definition

Potential difference, also known as voltage, is the work needed to move a charge from one point to another in an electric field. It is measured in volts (V).

5 Must Know Facts For Your Next Test

1. Potential difference drives current through a circuit.
2. It is calculated using Ohm's Law: $V = IR$, where $V$ is the potential difference, $I$ is the current, and $R$ is the resistance.
3. Potential difference can be measured using a voltmeter connected across two points in a circuit.
4. The unit of potential difference is the volt (V), which is equivalent to one joule per coulomb.
5. In direct-current (DC) circuits, potential difference remains constant over time.

Review Questions

• What equation relates potential difference to current and resistance?
• How would you measure the potential difference between two points in a circuit?
• What are the units of potential difference?

Related terms

Current:

The flow of electric charge in a conductor, typically measured in amperes (A).

Resistance:

The opposition to the flow of electric current, resulting in energy dissipation as heat, measured in ohms ($\Omega$).

Electromotive Force (EMF):

The energy provided by a source per coulomb of charge passing through it, often considered as the 'voltage' generated by a battery or generator.