Voltage
High School
Definition
The difference in electric potential energy per unit charge between two points in a circuit, measured in volts. Voltage acts like the 'push' that drives electric current through a conductor.
Worked examples
\(V = 9\,\)V\(\)
A 9-volt battery provides 9 joules of energy per coulomb of charge that flows through the circuit.
\(V = \frac{12\,\)J\(}{2\,\)C\(} = 6\,\)V\(\)
If 12 joules of energy moves 2 coulombs of charge, the voltage is 6 volts.
Common mistakes
- Voltage is the same as current → Voltage is the push; current is the flow of charge that results Voltage drives current, but they are different quantities measured in different units (volts vs amperes).
- Higher voltage always means more current → Current depends on both voltage and resistance: \(I = \frac{V}{R}\) A high-voltage circuit with high resistance can have low current.
- Voltage is 'used up' as current flows through a resistor → Energy is transferred; voltage drop measures the energy per charge lost Charge is conserved. Voltage drop indicates energy conversion (to heat, light, etc.), not loss of charge.
Where you'll use it next
You'll use voltage when analyzing series and parallel circuits, applying Ohm's law, studying electric power, and understanding how batteries, generators, and household electricity work in physics and engineering.
Found in 1 StudyPug lesson
Understanding Voltage in Electric Circuits
11th Grade11thPhysics 11
Dive into the world of voltage and electric circuits. Explore key concepts, laws, and real-world applications. Boost your electrical engineering skills with our comprehensive guide.
See also
Reviewed by Pat Cheng, M.Ed. — StudyPug Curriculum Lead · Last updated June 6, 2026