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UNIT OVERVIEW
This unit explores how electricity and magnetism work together in generators and motors. These machines power almost everything around us—from Eskom power stations to household appliances.
Key idea: Movement can create electricity (generators), and electricity can create movement (motors). These are reverse processes based on the same physics.
What You Will Learn
- The motor effect: forces on current-carrying conductors in magnetic fields
- How DC motors convert electrical energy to mechanical energy
- How AC and DC generators convert mechanical energy to electrical energy
- The difference between slip rings and split-ring commutators
- Root mean square (RMS) values for alternating current
- Power calculations in AC circuits
Key Terms for This Unit
| Term | Meaning |
|---|---|
| Motor effect | The force on a current-carrying conductor in a magnetic field |
| EMF | Electromotive force—the voltage produced by a generator or battery (measured in volts) |
| Torque | A turning force that causes rotation (measured in N·m) |
| Commutator | A device that reverses current direction in a motor or generator |
| RMS value | The effective value of AC that equals a DC value producing the same power |