Plan the investigation
What students will do
Use the student handout to organize predictions, measurements, and explanations.
- Predict both rotors. Calculate disk and hoop inertias, initial torque, and angular acceleration for matching masses and radii.
- Read initial values. Compare the paused starting-state torque and acceleration for both objects with your calculations.
- Change one input. Test the handout’s mass, radius, and force-position cases. Calculate each initial response before checking it.
- Explain the comparison. Connect inertia and lever arm with the results, then observe why torque changes as the attachment rotates.
What students will learn
- Distinguish mass from rotational inertia.
- Separate the effects of inertia and applied torque.
- Recognize when a comparison requires initial-state measurements.
Common misconception
Do equal mass and radius guarantee equal angular acceleration?
Different mass distributions can have different rotational inertias.