Rotational motion Mid UI

 2600 rev/min is equivalent to which of the following?

• 2600 rad/s 
• 43.3 rad/s 
• 273 rad/s
• 60 rad/s

For a rotating rigid body, which of the following statements is NOT correct?

• All points along a rotating rigid body move with constant speed
• Points along a rotating body have velocities that continuously change directions
• Points along a rotating body move through the same angle in equal time intervals
• All of the answers are correct

A body with a definite shape that doesn't change is:

• period

• angular acceleration

• rigid body

• radius of gyration

A solid sphere, solid cylinder, and a hollow pipe all have equal masses and radii. If the three of them are released simultaneously at the top of an inclined plane and do not slip, which one will reach the bottom first?

• cylinder
• pipe
• sphere
• They all reach the bottom at the same time.

A person sits on a freely spinning lab stool that has no friction in its axle. When this person extends her arms,

• her moment of inertia increases and her angular speed decreases.
• her moment of inertia decreases and her angular speed increases.
• her moment of inertia increases and her angular speed increases.
• her moment of inertia increases and her angular speed remains the same.

The drive chain in a bicycle is applying a torque of 0.850 N ∙ m to the wheel of the bicycle. You can treat the wheel as a thin uniform hoop (or ring) with a mass of 0.750 kg and a radius of 33.0 cm. What is the angular acceleration of the wheel?

• 10.4 rad/s²
• 3.43 rad/s²
• 5.20 rad/s²
• 1.06 rad/s²

If the translational velocity of an object is 3 m/s, and is located a distance of 2 m from the axis of rotation, what is the object's angular velocity?

• 0.67 rad/s
• 1.5 rad/s
• 5 rad/s
• 6 rad/s

Two rings have their moments of inertia in the ratio 2 : 1 and their diameters are in the ratio 2 : 1. The ratio of their masses will be..........

• 2 : 1

• 1 : 2

• 1 : 4

• 1 : 1

The bulging of the earth at the equator is due to ......

• centripetal force

• centrifugal force

• gravitational force

• electrostatic force

A circular disc rotates about an axis passing through its centre with a certain angular velocity. Suddenly a small piece of the disc breaks from the edge and falls down. Then ........

• its M.I. will increase and the angular velocity will decrease

• its M.I. will decrease and the angular velocity will increase

• both, the M.I. and the angular velocity will increase

• both, the M.I. and the angular velocity will decrease