Electronics is about controlling a current with a voltage or a signal. A diode controls direction, and a transistor lets a small current control a larger one.
This cluster is part of SPM Physics. It builds on electricity, especially potential dividers and Ohm’s law.
How do the lessons connect?
- Interpreting diode behaviour shows a one-way component.
- Explaining rectification uses diodes to turn a.c. into d.c.
- Reading transistor circuit functions adds control by a small base current.
- Explaining electron-beam and electronic-device principles covers how an oscilloscope shows the signals.
What does one idea look like in three devices?
A diode has two states: it conducts when the voltage across it is the right way round, and it blocks otherwise. A transistor also has two useful states, switched by a voltage at the base.
The oscilloscope lets you see those voltages on a screen. A rectified signal shows as a row of humps, and a transistor’s base voltage shows as a level that rises above or falls below the switching voltage. The same habit, reading a voltage and saying what it controls, works in every lesson.
Who should start where?
If the diode symbol and its direction are unclear, begin with lesson 1. If you can follow the devices but lose marks on an oscilloscope trace, go to lesson 4. Test the cluster with the practice set.
Electronics questions reward a clear sketch. Mark the direction of conventional current, label the voltages and state what each component does.
Use the mistake log to record which circuits you misread. If you want a teacher to work through your circuit sketches, see online one-to-one Physics tuition.