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 what translational kinetic energy is and why it uses the speed of the center of mass. (Guide: “Energy of motion”)
- I can explain why kinetic energy is a scalar that is never negative, and why moving left or right at the same speed gives the same K. (Guide: “Kinetic energy is a scalar”; Practice Q3)
- I can explain why the kinetic energies of objects in a system add, even when their velocities cancel. (Guide: “Kinetic energy is a scalar”; Practice Q7)
- I can explain why two observers in different frames can measure different kinetic energies for the same object. (Guide: Worked example 2; Practice Q3, Q7)
Calculation
- I can calculate K = ½mv² with correct units, and show that 1 J = 1 kg·m²/s². (Guide: “Energy of motion”; Practice Q1)
- I can find an object’s speed from its kinetic energy using v = √(2K/m). (Guide: Worked example 1; Practice Q4)
- I can predict the factor by which K changes when the mass or speed changes. (Guide: factor-of-change table; Practice Q2)
- I can calculate a change in kinetic energy by subtracting two kinetic energies, not by using ½m(Δv)². (Guide: Worked example 3)
Reasoning and representations
- I can sketch K against velocity and K against v², and state the slope of the straight-line graph. (Guide: Figure 1)
- I can sketch K against time for an object thrown straight up and explain why it touches zero at the top. (Practice Q5)
- I can choose what to plot so that kinetic-energy data give a straight line, and use the slope to test a claim. (Guide: linearising paragraph; Practice Q6)
- I can use K ∝ v² to explain why halving K does not halve the speed. (Practice Q4)
All ticked? Move on to Topic 3.2, Work, or return to the course roadmap.