All Flashcards
What is the effect of a skater pulling their arms inward during a spin?
The skater's moment of inertia decreases, causing their angular velocity to increase to conserve angular momentum.
What is the effect of applying an external torque to a rotating object?
The object's angular momentum will change.
What happens to the rod's angular speed if the disk bounces back in the disk and rod collision?
The rod's angular speed will be greater because the disk transfers more angular momentum to the rod.
What are the steps to solve a conservation of angular momentum problem?
1: Identify initial and final states. 2: Determine if external torque is zero. 3: Apply . 4: Solve for the unknown.
How does a skater conserve angular momentum?
1: Skater starts spinning with arms out (high , low ). 2: Skater pulls arms in (low ). 3: Angular velocity increases to conserve angular momentum ( remains constant).
Compare linear and angular momentum.
Linear momentum: mass in linear motion, conserved when no external forces act. Angular momentum: rotational inertia in rotational motion, conserved when no external torques act.
Differentiate between linear and angular velocity in planetary motion.
Linear velocity: changes as a planet orbits (faster closer to the star). Angular velocity: constant, ensuring equal areas are swept out in equal times (Kepler's 2nd Law).