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 explain why a torque on a body that does not turn transfers no energy. (Guide: “A torque transfers energy only through an angle”)
- I can decide whether the work done by a torque is positive, negative or zero from the senses of the torque and the rotation. (Guide: “Positive, negative and zero work”; Practice Q6(a))
- I can explain why torque and work share base units but are different quantities. (Guide: “From force work to torque work”)
Calculation
- I can derive dW = τ dθ from the work done by the tangential component of a force, using ds = r dθ. (Guide: Figure 1; Practice Q5(a))
- I can calculate the work done by a torque that depends on angle by integration. (Guide: Worked example 1; Practice Q1, Q4)
- I can find work as the signed area under a torque–angle graph, including estimates from data. (Guide: Figure 2; Practice Q2, Q6)
- I can derive the rotational work–energy theorem from τ_net = Iα with the chain rule. (Guide: “The rotational work–energy theorem”; Practice Q5(c))
- I can use net work to find a final angular velocity, including friction’s negative work. (Guide: Worked example 1; Practice Q4)
Reasoning
- I can derive symbolic results, such as the angle of greatest ω and the stopping angle, for a body acted on by several torques. (Guide: Worked example 2)
- I can compare work, kinetic energy and ω between bodies with different rotational inertias. (Guide: “Comparing scenarios”; Practice Q3)
- I can explain why equal angles do not give equal work when the torque changes with angle. (Practice Q7)
- I can use measured and predicted energies to estimate a friction torque. (Practice Q6(d))
All ticked? Move on to Topic 6.3, Angular Momentum and Angular Impulse, or return to the course roadmap.