Mistake Master · AP Physics C · Unit 5 · Topic 5.4 · Step-Through Animation
Rotational Inertia: Weight Every Bit by r²
Rotational inertia isn’t one fixed number — it’s the sum ∫r²dm, every scrap of mass weighted by the square of its distance from the axis. Slice a rod into dm, integrate to one-twelfth ML², then hop the axis to the end with the parallel-axis theorem and watch the shift add.
ROTATIONAL INERTIA
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