Remarks Although the angular momentum of the system is conserved, mechanical ene
ID: 1471100 • Letter: R
Question
Remarks Although the angular momentum of the system is conserved, mechanical energy is not conserved because the student does work on the system.
Question If the student suddenly releases the weights, how does his own angular momentum, rotational kinetic energy, and angular speed change? (Select all that apply.)
His rotational angular speed remains the same. His angular momentum increases. His rotational kinetic energy remains the same. His angular momentum remains the same. His rotational angular speed decreases. His angular momentum decreases. His rotational angular speed increases. His rotational kinetic energy increases. His rotational kinetic energy decreases.
Explanation / Answer
His angular momentum remains the same.
In this case, the law of conservation of angular momentum holds good. As student releases weights, the moment of inertia decreases ( since total inerita is proportional to mass ) and angular speed increases so as the total angular momentum of the system is constnat ( conservation).
Thus, the rotational angular speed increases and hence the rotational kinetic energy increases.