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1. How can skaters make themselves spin faster?

2. How many radians is 575 degrees?

3. If something spins at 200 RPM what is the period of revolution?

4. How does angular acceleration relate to linear acceleration?

5. To get up on the roof, a person (mass 70.0 kg) places a 6.00-m aluminum ladder (mass 10.0 kg) against the house on a concrete pad with the base of the ladder 2.00 m from the house. The ladder rests against a plastic rain gutter, which we can assume to be frictionless. The center of mass of the ladder is 2 m from the bottom. The person is standing 3 m from the bottom. What are the magnitudes of the forces on the ladder at the top and bottom?

6. What is the mechanical advantage of a nail puller where you exert a force

45 cm from the pivot and the nail is 1.8 cm on the other side? What minimum force must you exert to apply a force of 1250 N to the nail?

7. Suppose you needed to raise a 250-kg mower a distance of 6.0 cm above the ground to change a tire. If you had a 2.0-m long lever, where would you place the fulcrum if your force was limited to 300 N?What is 300N in lbs? Where is the fulcrum in inches from the place where the force is applied?

8. What is the mechanical advantage of a wheelbarrow if the center of gravity of the wheelbarrow and its load has a perpendicular lever arm of 3", while the hands have a perpendicular lever arm of 3'? What upward force should you exert to support the wheelbarrow and its load if their combined weight is 150 lbs? What force does the wheel exert on the ground?

9. At its peak, a tornado is 60.0 m in diameter and carries 500 km/h winds. What is its angular velocity in revolutions per second?

10. A gyroscope slows from an initial rate of 32.0 rad/s at a rate of 0.700

rad/s². How long does it take to come to rest? How many revolutions does it make before stopping?

11-15. During a very quick stop, a car decelerates at 7.00 m/s². What is the angular acceleration of its 0.280-m-radius tires, assuming they do not slip on the pavement? How many revolutions do the tires make before coming to rest, given their initial angular velocity is 95.0 rad/s ? How long does the car take to stop completely? What distance does the car travel in this time? What was the car's initial velocity?