Exam 11: Rolling, Torque, and Angular Momentum

A 2.0-kg block travels around a 0.50-m radius circle with an angular velocity of 12 rad/s. The magnitude of its angular momentum about the center of the circle is:

Two wheels roll side-by-side without sliding, at the same speed. The radius of wheel 2 is twice the radius of wheel 1. The angular velocity of wheel 2 is:

A 2.0-kg stone is tied to a 0.50-m long string and swung around a circle at a constant angular velocity of 12 rad/s. The net torque on the stone about the center of the circle is:

Two objects are moving in the x, y plane as shown. The magnitude of their total angular momentum (about the origin O) is:

A wheel, with rotational inertia I, mounted on a vertical shaft with negligible rotational inertia, is rotating with angular speed $\omega$ _0. A nonrotating wheel with rotational inertia 2I is suddenly dropped onto the same shaft as shown. The resultant combination of the two wheels and shaft will rotate at:

A hoop rolls with constant velocity and without sliding along level ground. Its rotational kinetic energy is:

Two objects are moving in the x, y plane as shown. If a net torque of 44 N∙m acts on them for 5.0 seconds, what is the change in their angular momentum?

A pulley with radius R and rotational inertia I is free to rotate on a horizontal fixed axis through its center. A string passes over the pulley. A block of mass m₁ is attached to one end and a block of mass m_2, is attached to the other. At one time the block with mass m₁ is moving downward with speed v. If the string does not slip on the pulley, the magnitude of the total angular momentum, about the pulley center, of the blocks and pulley, considered as a system, is given by:

A force = 4.2 N + 3.7 N + 1.2 N acts on a particle located at x = 3.3 m. What is the torque on the particle around the origin?

When a man on a frictionless rotating stool extends his arms horizontally, his rotational kinetic energy:

A thin-walled hollow tube rolls without sliding along the floor. The ratio of its translational kinetic energy to its rotational kinetic energy (about an axis through its center of mass) is:

When we apply the energy conversation principle to a cylinder rolling down an incline without sliding, we exclude the work done by friction because:

The unit kg.m²/s can be used for:

A 5.0-kg ball rolls without sliding from rest down an inclined plane. A 4.0-kg block, mounted on roller bearings totaling 100 g, rolls from rest down the same plane. At the bottom, the block has:

The coefficient of static friction between a certain cylinder and a horizontal floor is 0.40. If the rotational inertia of the cylinder about its symmetry axis is given by I = (1/2)MR², then the maximum acceleration the cylinder can have without sliding is:

A particle moves along the x axis. In order to calculate the angular momentum of the particle, you need to know:

Two pendulum bobs of unequal mass are suspended from the same fixed point by strings of equal length. The lighter bob is drawn aside and then released so that it collides with the other bob on reaching the vertical position. The collision is elastic. What quantities are conserved in the collision?

What is precession?

A 6.0-kg particle moves to the right at 4.0 m/s as shown. The magnitude of its angular momentum about the point O is:

A 2.0-kg block travels around a 0.50-m radius circle with an angular speed of 12 rad/s. The circle is parallel to the xy plane and is centered on the z axis, 0.75 m from the origin. The component in the xy plane of the angular momentum around the origin has magnitude: