Safety boundary
Use only low-voltage classroom batteries/components under supervision or an approved circuit simulation. Never use mains voltage.
Explicit physics instruction
A circuit investigation should preserve measured or simulated V and I pairs before fitting a model.
For an ohmic resistor, V versus I should be approximately linear with slope R.
Series/parallel predictions can be tested by comparing total current and branch behavior.
Core relation/model: slope of V vs I ≈ R
Worked example
If V/I values remain near 5 Ω across several trials, the data support an ohmic model over that range.
Guided question
What graph best tests whether resistance is approximately constant?
Independent work
- Preserve raw V/I data.
- Graph V versus I.
- Estimate resistance from slope.
- Compare one series/parallel prediction and record a residual.
Investigation / Data Lab
Use a circuit simulation or supervised low-voltage setup to compare voltage, current, resistance, series/parallel behavior, and power.
Preserve raw data, calculations, graph/model comparison, uncertainty, and one revision.
Misconception check
A single V/I point cannot establish linear ohmic behavior across a range.
Formative check
What does the slope of a V-versus-I graph represent for an ohmic resistor?
Reveal response
Resistance.
Mentor evidence conference
Ask Archaemenes to audit units, assumptions, model selection, and whether the evidence supports the conclusion.
Teacher guidance
Foundation: Use supplied simulated data.
Core: Fit/interpret V-I data and network behavior.
Extended: Analyze uncertainty or nonlinearity.