Voltage
Also known as: potential difference, EMF, V
The difference in electric potential energy per unit charge between two points. Without voltage, there's no current — voltage is the driving force of every circuit.
💡 Intuition
Voltage is like water pressure — it's the 'push' that drives current through a circuit.
Core Idea
Voltage is the energy per coulomb available to push charges through a circuit.
Formal View
🔬 Example
🎯 Why It Matters
Without voltage, there's no current — voltage is the driving force of every circuit.
⚠️ Common Confusion
Voltage exists between two points (it's a difference), not at a single point.
💭 Hint When Stuck
When solving a voltage problem, first identify the two points between which the potential difference is measured. Then use V = W/Q if energy and charge are given, or V = IR (Ohm's law) if current and resistance are known. Finally, check the direction: current flows from higher to lower potential through a resistor.
Related Concepts
Prerequisites
Next Steps
How Voltage Connects to Other Ideas
To understand voltage, you should first be comfortable with electric current. Once you have a solid grasp of voltage, you can move on to resistance, ohms law and potential difference.
Go Deeper
Frequently Asked Questions
What is Voltage in Physics?
The difference in electric potential energy per unit charge between two points. Measured in volts (V).
Why is Voltage important?
Without voltage, there's no current — voltage is the driving force of every circuit.
What do students usually get wrong about Voltage?
Voltage exists between two points (it's a difference), not at a single point.
What should I learn before Voltage?
Before studying Voltage, you should understand: electric current.