Rotational Momentum

What happens to her rotational inertia when a figure skater brings in her arms?

• Increase her rotational inertia
• Decrease her rotational inertia
• has no affect

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

• A high rotational inertia
• A low rotational inertia
• A low linear acceleration
• A 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.MS-PS3-1

A bicycle wheel is spun from rest to 15 revolution a second.  What is the time required to do this if its moment of inertia is 0.050 kg*m^2 and it was given a torque of 5 Nm?

• 9.42 seconds
• 0.942 seconds
• 1.58 seconds
• 1.24 seconds

A disk is spinning with an angular velocity of 15 rads / second.  If it takes 10 seconds to increase its angular velocity to 25 rads / second, what is the torque required if its moment of inertia is 0.95 kg*m^2?

• 1.5 Nm
• 0.95 Nm
• 19 Nm
• 9.5 Nm

Tags

NGSS.HS-PS2-1