Electrical Engineering › Section A · Introduction, current, and voltage › Topic A.2
Atoms, current, and voltage
Every circuit runs on two ideas: current, the rate at which charge moves, and voltage, the energy each unit of charge gains or loses. Both start inside the atom, with electrons that some materials hold tightly and others let wander.
In this topic
- Inside the atom
- Why copper conducts
- Charge and Coulomb's law
- Current: the rate of charge flow
- Conventional current and electron flow
- Worked example: current from counted charge
- Voltage: energy per charge
- Voltage is always between two points
- Worked example: charge and energy from a charger
- Common mistakes to avoid
- Key takeaways
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