1. Consider an object that is rotating with a constant angular velocity w. Which of the following statements must be true? a. A constant torque is needed for this object to maintain its rotational motion. b. Since the angular velocity of the object is not changing, there must be no external torques acting upon the object. If a single external torque is applied to the object, then the object will have an angular c. acceleration a. d. Since the object does not have an angular acceleration, then it must be in mechanical equilibrium.

A frisbee is moving through the air with a constant angular velocity of 10 cycles/s and a constant center of mass velocity of 20 m/s. Which of the following statements is true.   a. The frisbee is not in rotational equilbrium.   b. The frisbee is in total equilibrium.   c. The frisbee is not in translational equilibrium, and it is not in rotational equilibirum.   d. The frisbee is not in translational equilibrium.   e. The frisbee is in translational equilibrium, but it is not in rotational equilibirum.

5. A6 ft board with mass of 2 kg is horizontal and attached to a swivel on one side,the other is allowed to fall from rest. (One side of the board will fall| while the other stays fastened..)

A. less than initial angular momentum before the person moves B. same as initial angular momentum before the person moves C. greater than initial angular momentum before the person moves

3. A rowing machine consists of a solid disk with a radius of 20-cm and a mass of 19-kg. An athlete pulls on the attached cable with a force of 10-Newtons and causes the disk to accelerate. If the disk starts from rest, determine; a. The disk's moment of inertia. b. The magnitude of the torque applied by the athlete. C. The disk's angular acceleration. d. The disk's angular momentum at t = 5.0 sec.

2. Calculate the moment of inertia of a rectangular plate that is 24.0 cm long and 12.0 cm wide, with a mass of 1.25 kg, a. for an axis of that is perpendicular to the plate passing through its center. b. for an axis along its long edge. c. for an axis along its short edge.

A force F is applied perpendicular to a rod at a distance l away from the axis of rotation. Which of the following is TRUE about the torque on the rod? Explain why.A. Torque is parallel to force FB. The longer the lever arm, the smaller the torque. C. When the magnitude of F is doubled, the torque is halved. D. Torque is perpendicular to the lever arm

An ice skater is spinning on the ice with her arms fully extended. When she pulls in her arms, she spins at a faster rate because     a. Her moment of inertia decreases.     b. Her moment of inertia increases.     c. Her moment of inertia stays the same.     d. Her mass stays the same.     e. Her weight stays the same.

An ice skater, whose rotational inertia is I = 4 kg·m2 with her arms close to her body, is spinning at 2 rad/s. She then fully extends her arms, changing her rotational inertia to 8 kg·m2. Which of the following is true? a.) Her angular momentum remains the same. b.) Her angular velocity decreases.     c.) Her kinetic energy decreases. d.) All of the above. e.) B and C. d.) None of the above.

Two objects, a sphere and a block of the same mass, are released from rest at the top of an inclined plane. The sphere rolls down the inclined plane without slipping. The block slides down the plane without friction. Which object reaches the bottom of the ramp first? A. The sphere, because it gains rotational kinetic energy, but the block does notB. The sphere, because it gains mechanical energy due to the torque exerted on it, but the block does notC. The block, because it does not lose mechanical energy due to friction, but the sphere doesD. The block, because it does not gain rotational kinetic energy, but the sphere does