alleryStart learning →Angular momentum is a vector. Is rotational kinetic energy also a vector?
AYes, it points along the rotation axis
BNo, every form of energy is a scalar
CYes, it points along the rim velocity
DNo, only linear kinetic energy is scalar
Answer & Solution
Correct answer: B. No, every form of energy is a scalar
1. Energy is always a scalar, whether or not motion is involved.
2. No form of energy has a direction in space.
3. Rotational kinetic energy is one half I omega squared, and squaring omega removes any sense of direction.
4. Linear kinetic energy is a scalar for the same reason, so the last option draws a false distinction.
_Source: OpenStax College Physics (CC BY 4.0), Ch 10 "Rotational Motion and Angular Momentum", section 10.7 Gyroscopic Effects: Vector Aspects of Angular Momentum_
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