16. Angular Momentum

Which of the following expressions correctly gives the angular momentum of a particle of mass $m$ moving with velocity $v$ at a position vector $r$ relative to the origin?

A circular coil of radius $R$ and moment of inertia $I$ is placed in a uniform magnetic field $B$. The coil is free to rotate about its axis, which is perpendicular to the magnetic field. If a current $I$ (current, not moment of inertia) is suddenly started in the coil, what is the initial angular acceleration $\alpha$ of the coil just after the current is started?

Two turbines, A and B, are rotating at constant angular speeds. Turbine A has an angular speed of $\omega =2.0$ rad/s, and turbine B has an angular speed of $\omega =3.0$ rad/s. If both start at the same time, which turbine takes less time to rotate through an angular displacement of $1.0$ radian?

A block of mass $m$ is attached to a light string wound around a solid cylinder of mass $M$ and radius $R$. The cylinder rotates freely about its horizontal axis. When the block is released and descends, what is the magnitude $\alpha$ of the angular acceleration of the cylinder?

Which of the following best describes the difference between linear momentum and angular momentum?

Which of the following quantities contribute to the angular momentum of a spinning object?

A toy gyroscope consists of a 170-g disk with a radius of 5.5 cm mounted at the center of a thin axle 21 cm long (Fig. 11–42). The gyroscope spins at 45 rev/s. One end of its axle rests on a stand and the other end precesses horizontally about the stand. How long does it take the gyroscope to precess once around?