16. Angular Momentum

What is the angular momentum of a hydrogen atom in a 4p state? Give your answer as a multiple of $\hslash$.

When a bullet spins as it is fired from a rifled barrel, what property of its motion is primarily improved?

Two disks are mounted on the same axis. Disk 1 has a moment of inertia $I_i$ and initial angular velocity ${\omega }_i$. Disk 2, initially at rest, has a moment of inertia $I_r$. If the disks are suddenly coupled together so that they rotate as one unit without external torques, what is the final angular velocity ${\omega }_f$ in terms of $I_i$, $I_r$, and ${\omega }_i$?

Given a rotating object that moves through an angular displacement of $\Delta \theta$ in a time interval $\Delta t$, what is the formula for its average angular speed?

A person of mass $m$ stands at the edge of a frictionless circular platform of mass $M$ and radius $R$, initially at rest. The person walks to the center of the platform. Assuming no external torques act on the system, what is the angular velocity $\omega f_{}$ of the platform after the person reaches the center?

What is the approximate angular speed of the Earth as it rotates about its axis? (Assume one rotation per $\mathrm{sidereal}\mathrm{day}$.)

A clock's minute hand is $0.15 m$ long. What is the angular speed of the tip of the minute hand in radians per second?

Angular momentum measures which of the following physical quantities for a rotating object?

In a rotating solar nebula, where is the angular velocity $\omega$ slowest?

An object's angular momentum is proportional to its $?$.

Why do you expect neutron stars to spin more rapidly than white dwarfs?

Which of the following statements does not use the term angular size or angular distance correctly?

Given that the average diameter of the Moon is approximately $\mathrm{3,474}$ km and its average distance from Earth is about $\mathrm{384,400}$ km, what is the Moon's angular size as seen from Earth in arcseconds?

A uniform door of mass $M$ and width $w$ is initially at rest and free to rotate about its hinges. A small ball of mass $m$ traveling at speed $v$ strikes the edge of the door perpendicularly and sticks to it. What is the angular velocity $\omega$ of the door (with the ball attached) just after the collision?

How is the angular displacement $\theta$ related to the angular velocity $\omega$ for an object rotating at constant angular velocity?