Rotational Kinematics
A spinning disk. A record on a turntable. A wheel on an axle. Different shapes, same physics: every point on the body sweeps the same angle in the same time. To describe that motion you need three quantities ($\theta$, $\omega$, $\alpha$) and four equations. The equations are the Unit 1 kinematic equations with rotational letters swapped in.
Three traps to watch for. Rim versus hub: the outside of a spinning disk covers more arc per second than the hub, so it feels like it should have a bigger $\omega$. It doesn't. Every point on a rigid body shares one $\omega$ and one $\alpha$. Omega versus alpha: a big $\omega$ tells you nothing about $\alpha$, and a big $\alpha$ tells you nothing about $\omega$. They're independent. Sign convention: a negative $\omega$ is not "stopped," it just points the other way. Pick a positive direction at the start and keep it for the whole problem.
The work
3 ways in · any order
Lesson
Rotational Kinematics
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Three quantities ($\theta$, $\omega$, $\alpha$), four equations (the Unit 1 ones with rotational letters), three graphs to read at a glance. Closes with a ten-scenario applet that hits all three of the topic's pitfalls.
Diagnostic
10-item topic check
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Ten items on $\theta$, $\omega$, $\alpha$, the four equations, and the three angular graphs. Each wrong-answer chip is wired to one of the topic's pitfalls, so a missed item tells you exactly what to drill. Take it cold to find your gaps, or after the lesson to check yourself.
Targeted Practice
Drill a single misconception
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Pick one of the failure modes you've missed and grind it on its own. The round is adaptive: two correct in a row clears the misconception and you move on.