Appendix 2: Teacher notes - outputs of the lesson

Syllabus section addressed by this lesson

Teaching Syllabus for Physics (SHS 1–3)

SHS2 Mechanics Section 5 Electricity and magnetism

Unit 1 Direct current analysis

The Electrical circuits application is split into three sections, and each is accessed via the application homepage.

The first and second sections look at the behaviour of carbon resistors in an electrical circuit.

The resistors used have a tolerance of ±5% and each resistor has a resistance that conforms to this standard. The application is designed so that within this range each student will have a selection of resistors that will vary – much as it would in a physical laboratory. Students will have a choice of using a 9 V or 1.5 V battery – because the focus is on the behaviour of resistors (in series and parallel), we have opted to maintain a stable voltage across the resistors. Given the straightforward nature of these two sections and the background and guidance provided to students in the lesson, we have not provided further details here.

The final section explores resistance in three 1 m lengths of nichrome wire with varying cross-sectional areas.

The battery used in this section is rated at 9 V, but the voltage recorded in the circuit will vary according to the current load. The wires will also heat-up at shorter lengths, as they might in a laboratory setting. The thick wire has a diameter which is twice that of the medium wire, and the thin wire has a diameter which half that of the medium wire.

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