alleryStart learning →What is the rotational kinetic energy of a body with moment of inertia I turning at angular velocity omega?
AHalf I omega squared
BHalf I squared omega
CI omega squared
DTwo I omega squared
Answer & Solution
Correct answer: A. Half I omega squared
1. Translational kinetic energy is one half m v squared.
2. The rotational analogue replaces m by I and v by omega.
3. So the rotational kinetic energy is one half I omega squared.
4. Squaring I instead of omega would give the wrong units and break the analogy.
_Source: OpenStax College Physics (CC BY 4.0), Ch 10 "Rotational Motion and Angular Momentum", section 10.4 Rotational Kinetic Energy: Work and Energy Revisited_
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