A person holds a spinning bicycle wheel while sitting stationary on a chair that is free to rotate about a vertical axis. As the person changes the axis of the spinning bicycle wheel, the chair begins to rotate about its axis. The chair's rotation is a result of:
  1. Conservation of angular momentum.
  2. A torque due to the force of gravity.
  3. Conservation of rotational kinetic energy.
  4. The mechanical advantage of double-axis rotational system.
Explanation
Correct Response: A. Angular momentum is a vector quantity. The conservation of angular momentum accounts for the rotation of the chair that takes place with a vector angular momentum, which when added to the final vector angular momentum of the wheel equals the initial vector angular momentum of the wheel. Answer choice B could be used to explain the precession of the bicycle wheel if it were held by only one end of its rotational axis, but it does not help explain the rotation of the chair in this case. Answer choice C does not apply, since rotational kinetic energy is not conserved. Answer choice D does not explain the rotation of the chair, although the chair-wheel system does involve two axes of rotation.
Was this helpful? Upvote!
Login to contribute your own answer or details

Top questions

Related questions

Most popular on PracticeQuiz