Energy and Momentum of Rotating Systems unit test
A test on this unit alone, marked as a percentage and a letter grade — for the test your class is actually sitting, rather than for May. Answer everything, then submit once: seeing the answer to question 3 before attempting question 4 makes the final percentage meaningless.
Angular momentum
A particle moving in a straight line has angular momentum
Torque, angular momentum and the second law
Fraction of a rolling sphere's energy that is rotational
The condition for angular momentum conservation
K = ½(1 + c)mv² for a rolling body
Racing shapes down a ramp
Angular momentum of a particle
Moment of inertia depends on the axis
Rotational collisions
Total kinetic energy of a rolling object
Why the skater gains kinetic energy
Short answer 1. Define or explain: Angular momentum in orbits
3 ptsShort answer 2. Define or explain: Angular impulse
3 ptsShort answer 3. Define or explain: When to use energy vs angular momentum
3 ptsShort answer 4. Define or explain: Where to strike a pivoted rod for maximum effect
3 ptsFree response
7 ptsA solid disk and a hollow hoop have the same mass M and radius R. Both are released from rest at the top of an incline of height h and roll without slipping to the bottom. (a) Explain, without calculation, why both objects arrive with less translational speed than a frictionless sliding block released from the same height. (b) Derive an expression for the translational speed at the bottom in terms of M, R, h, g and the moment of inertia I. (c) Use your expression to determine which object arrives first, and justify why the result does not depend on M or R.
Explain, without calculation, why both objects arrive with less translational speed than a frictionless sliding block released from the same height.
Derive an expression for the translational speed at the bottom in terms of M, R, h, g and the moment of inertia I.
Use your expression to determine which object arrives first, and justify why the result does not depend on M or R.