A figure skater pulls in her arms while spinning. What happens to her angular ve
Practice Questions
Q1
A figure skater pulls in her arms while spinning. What happens to her angular velocity?
Increases
Decreases
Remains the same
Becomes zero
Questions & Step-by-Step Solutions
A figure skater pulls in her arms while spinning. What happens to her angular velocity?
Step 1: Understand that a figure skater spins with arms out and then pulls her arms in.
Step 2: Know that when she pulls her arms in, her shape changes, which affects her moment of inertia.
Step 3: Remember that moment of inertia is a measure of how spread out the mass is from the center of rotation.
Step 4: Realize that pulling in her arms makes her moment of inertia decrease because her mass is closer to the center.
Step 5: Learn about the conservation of angular momentum, which states that if no external forces act on a system, the total angular momentum remains constant.
Step 6: Since her moment of inertia decreases, her angular velocity must increase to keep the angular momentum constant.
Conservation of Angular Momentum – The principle that the total angular momentum of a closed system remains constant if no external torques act on it.
Moment of Inertia – A measure of an object's resistance to changes in its rotation, which depends on the mass distribution relative to the axis of rotation.
Angular Velocity – The rate of rotation of an object around an axis, typically measured in radians per second.