Safety boundary
Use simulations, supplied data, and ordinary classroom-static examples only. Do not use mains electricity or improvised high-voltage devices.
Explicit physics instruction
This investigation uses simulation or supplied data only—no high-voltage devices.
Measure field magnitude at several distances from one modeled charge, then compare E with 1/r².
Add a second source charge and compare measured field direction with qualitative vector superposition.
Vocabulary: simulation; field map; inverse-square fit; superposition; residual.
Worked example
If E=900 N/C at r=1 unit, ideal inverse-square prediction at r=3 is 100 N/C.
Guided question
Which transformed graph would help test E∝1/r² most directly?
Independent work
- Preserve raw r and E data.
- Calculate 1/r² for each point.
- Graph E versus 1/r².
- Add a second source and compare vector prediction with the simulated field.
Investigation / Data Lab
Use simulation or supplied data only. Preserve raw values, transformed quantities, graph, residuals, uncertainty, and one revision.
Misconception check
A visually curved E-versus-r graph can still represent a precise inverse-square relationship.
Formative check
What would support the inverse-square model?
Reveal response
A near-linear relationship between E and 1/r² with small residuals.
Mentor evidence conference
Ask Archaemenes to audit sign conventions, vector/scalar distinctions, units, and model assumptions.
Teacher guidance
Foundation: Use supplied values if simulation access is limited.
Core: Test inverse-square scaling and field direction.
Extended: Fit a line to E vs 1/r² and discuss residuals/uncertainty.