• #### 2.  Suppose you are designing an engineless car for a downhill coasting race. What type of wheels would be the best?

• Solid disks.
• Hoops.
• Hollow cylinders.
• Diamond encrusted triangles.

• True
• False

• r = v⍵
• ⍵ = vr
• v = r⍵
• a = v⍵
• #### 6.  A dancer on ice spins faster when she folds here arms. This is due to

• Increases in energy and increase in angular momentum
• Decrease in friction at the skates
• Constant angular momentum and increase in kinetic energy
• Increase in energy an decreases in angular momentum
• #### 7.  Centripetal acceleration is directed

• directed away from the center of the circle
• directed towards the center of the circle
• it is perpendicular to the radius at that point
• It has no direction

• 1 m/s
• 2 m/s
• 4 m/s
• 8 m/s
• #### 9.  Moment of inertia depends on

• Distribution of particles
• Mass
• Position of axis of rotation
• All of these

• I1 > I2
• I1 >> I2
• I1 < I2
• I1 = I2

• [M1 L2 T-1]
• [M1 L1 T-1]
• [M1 L1 T-2]
• [M1 L2 T-2]
• #### 12.  As global warming occurs over the next century, the polar ice caps will start to melt ant the water will be distributed closer to the equator. How will this change the Earth's moment of inertia?

• It would increase.
• It would decrease.
• It would stay the same.
• All of above