Rotational Motion and Rotational Dynamics

Analogue of mass in rotational motion is

• moment of inertia

• radius of gyration

• torque

• angular momentum

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

Determine the linear velocity of the tips of the blades in meters per second for a ceiling fan with 50 cm blades rotating at 45 rpm.

• 2.4 m/s

• 2300 m/s

• 8500 m/s

• 240 m/s

Which has more rotational inertia? (consider all objects have equal radius)

• Hollow sphere

• solid sphere

• cylindrical shell

• solid cylinder

Which has greater linear speed, a horse near the outside rail of a merry-go-round or a horse near the inside rail?

• the inside horse

• the outside horse

• Neither

In order to do a lot of flips an Olympic diver would want:

• high rotational inertia

• low rotational inertia

• low linear acceleration

• low angular velocity

Why are you more stable when riding a bicycle at a faster speed?

• You have more mass

• The wheels have angular momentum

• It's not easier to ride at a faster speed

• The bike has more momentum

Tags

NGSS.HS-PS2-2

Does a bridge anchored resting on two pillars have any torque?

• No, it isn't moving

• Yes, but it is at equilibrium

• Yes, but it will soon break because of the torque

• No, Bridges can't have torque

What is the angular velocity of a wheel rotating at 60 revolutions per minute (rpm)?

Which of the following quantities is conserved in an isolated system undergoing rotational motion?

• Angular momentum

• Angular velocity

• Torque

• Moment of inertia