6.2 Conservation Laws in Rotational Motion

• What is angular momentum conserved when no external torques act on a system?

  Total angular momentum remains constant
• Angular momentum and linear momentum are both measures of motion but describe different aspects of it.


  True
• In which scenario is conservation of angular momentum applied in rotating systems?

  Spinning figure skater
• The equation for conservation of rotational kinetic energy is K_initial = K_final
• Angular momentum is conserved unless external torques act on the system.
• Applying conservation laws in rotational motion can help solve problems related to rotating systems.


  True
• External torques are torques applied from outside the system
• A spinning figure skater increases their spin rate by pulling their arms inward.
• Angular momentum is related to linear momentum through the formula: Angular Momentum = Radius x Linear Momentum.

  True
• The equation for conservation of angular momentum is L_initial = L_final
• Angular momentum is conserved in a system when no external torques are applied.
• Conservation of rotational kinetic energy states that the total rotational kinetic energy of a system remains constant unless external work is done on it.

  True
• When is rotational kinetic energy conserved in a system?

  No external work is done
• What happens to angular momentum when no external torques act on a system?

  Total angular momentum remains constant
• What are the factors that affect angular momentum?

  Mass, rotational speed, radius
• The equation for conservation of angular momentum is L_initial = L_final
• The formula for linear momentum is p = mv
• What is an example of angular momentum conservation in real life?

  A spinning top
• The direction of angular momentum is a vector in the direction of motion

  False
• Match the condition with its description:

  Closed System ↔️ Isolated from external influences

  No External Torques ↔️ No torques applied from outside
• What is the equation for conservation of angular momentum?

  $L_{initial} =$$L_{final}$
• Match the feature with its corresponding type of momentum:

  Formula: $L =$$I\omega$ ↔️ Angular Momentum

  Formula: $p =$$mv$ ↔️ Linear Momentum
• What does a closed system in conservation of angular momentum mean?

  No external forces
• The principle of conservation of angular momentum is derived from the conservation of linear momentum.


  True
• Under what conditions is rotational kinetic energy conserved?

  No external torques do work
• What does the conservation of rotational kinetic energy state?

  KE remains constant
• What does $KE_{rot initial}$ represent in the conservation of rotational kinetic energy equation?


  Initial rotational KE
• Why does a spinning top with an initial KE of 500 joules eventually slow down?

  Friction
• The equation for conservation of angular momentum is $L_{initial} =$$L_{final}$
• A figure skater spinning faster when they pull their arms inward demonstrates conservation of angular momentum.


  True
• What two conditions are required for angular momentum to be conserved in a system?

  Closed system, no external torques
• In rotating systems, angular momentum depends only on mass and rotational speed.

  False
• The conservation of rotational kinetic energy states that in a closed system with no external torques, the total rotational kinetic energy remains constant.
• Angular velocity is the rate at which an object rotates
• Factors affecting angular momentum in order of their impact:

  1️⃣ Mass

  2️⃣ Rotational Speed

  3️⃣ Radius of Rotation
• Higher mass increases angular momentum
• What is the equation for conservation of angular momentum?

  $L_{initial} =$$L_{final}$
• Angular momentum is related to linear momentum through the formula: Angular Momentum = Radius x Linear Momentum
• The formula for angular momentum is $L =$$I\omega$, where $I$ is the moment of inertia and $\omega$ is the angular velocity
• Conditions required for angular momentum to be conserved

  1️⃣ The system is a closed system

  2️⃣ No external torques are applied