alleryStart learning →Are the rotational kinematic relations laws of nature or descriptions of motion?
ADescriptions only, since they ignore causes
BLaws, since they apply to every turning body
CLaws, since they follow from conservation rules
DDescriptions only, since they need calculus
Answer & Solution
Correct answer: A. Descriptions only, since they ignore causes
1. Kinematics is the description of motion without regard to force or mass.
2. The rotational equations relate theta, omega, alpha and t, and never mention what caused the motion.
3. They are therefore descriptive rather than laws of nature, exactly like linear kinematics.
4. Dynamics, which brings in torque and moment of inertia, is where the causal law appears.
5. Needing calculus is irrelevant, since these forms are algebraic for constant alpha.
_Source: OpenStax College Physics (CC BY 4.0), Ch 10 "Rotational Motion and Angular Momentum", section 10.2 Kinematics of Rotational Motion_
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