NCERT · Class 11 · Physics · System of Particles and Rotational MotionIf no external torque acts on a rotating system, which of the following physical quantities remains constant?
Step-by-Step Solution
According to the principle of conservation of angular momentum, when the net external torque acting on a system is zero, its total angular momentum remains constant ($\tau_{ext} = \frac{dL}{dt} = 0 \implies L = \text{constant}$).
Detailed Options Breakdown
Option : Angular momentum (Correct Answer)
Correct choice. Refer to the step-by-step verified solution guidelines above for details.
Option 1: Angular velocity
Incorrect choice. This distractor represents a common misunderstanding of the core principles of System of Particles and Rotational Motion.
Option 2: Moment of inertia
Incorrect choice. This distractor represents a common misunderstanding of the core principles of System of Particles and Rotational Motion.
Option 3: Rotational kinetic energy
Incorrect choice. This distractor represents a common misunderstanding of the core principles of System of Particles and Rotational Motion.
💡 Study Guide: This question tests core syllabus concepts from System of Particles and Rotational Motion. For formulas, key summaries, and mock exam reference guides, read the full System of Particles and Rotational Motion Revision Notes.