Work through the list without notes. If you cannot do a statement, follow its link, then come back. Guide = study guide; Practice = practice questions.
Understanding
- I can state when a rigid system’s angular velocity changes, and explain that α has the sense of the net torque, not of the rotation. (Guide: “Newton’s second law in rotational form”; Practice Q2)
- I can derive Στ = Iα from F = ma applied to each piece of a rigid system, and explain why internal torques cancel. (Guide: “Where Στ = Iα comes from”)
- I can explain why a_cm = ΣF/M and α = Στ/I must be written as separate equations. (Guide: “Linear and rotational analyses are separate”; Practice Q4(c))
Calculation
- I can predict the factor by which α changes when the torque, the mass or the size of an object changes. (Guide: “Using functional dependence”; Practice Q1)
- I can use the parallel axis theorem to find I for an off-center axle, then find α, a_cm and the axle force. (Guide: Worked example 1; Practice Q4)
- I can integrate a time-dependent net torque to find ω(t) and θ(t), and find when ω is greatest. (Guide: Worked example 2; Practice Q3)
- I can write one equation per object for a pulley with hanging masses and derive α in symbols. (Practice Q5)
Reasoning
- I can correct a hanging-mass tension for acceleration and include a friction torque when measuring I from a graph. (Guide: “Measuring rotational inertia in the lab”; Practice Q6)
- I can model a torque that depends on ω by separating variables, and explain why constant-α reasoning fails for it. (Practice Q7)
- I can check a result with special cases, such as an axle at the center of mass or a balanced stepped pulley giving α = 0. (Guide: Worked example 1; Practice Q5(c))
All ticked? Move on to Topic 6.1, Rotational Kinetic Energy, or return to the course roadmap.