Plan the investigation
What students will do
Start with a guided comparison, then plan an investigation, analyze a graph, and check a prediction.
- Compare mass distributions. Change the disk’s inertia factor and measure acceleration, speed, and angular velocity. Check the rolling condition.
- Design and collect. Choose at least five inertia factors while keeping mass, radius, and ramp geometry fixed.
- Analyze a linear graph. Transform inertia-factor and acceleration data to test the rolling model and infer gravitational acceleration.
- Explain and predict. Connect rotational inertia with downhill acceleration, then predict and test an unused inertia factor.
What students will learn
- Check rolling without slipping with speed and angular velocity.
- Distinguish mass distribution from total mass.
- Combine rotational and translational dynamics in a graph-based model.
Common misconception
Do equal mass and radius guarantee equal rolling acceleration?
The inertia factor describes how mass distribution changes the rolling response.