Honors Physics

# Questions - Week 21

1. If a person on a bicycle rode past you, moving to your right, what are the directions of the linear and angular velocities of the bike's wheels?
2. Is angular velocity a scalar or vector property?
3. What does it mean to say the efficiency of something is 65%?
4. How many Joules are used by a 75.0 W light bulb over 24.0 hours?
5. Why is it wrong to say a 75 W light bulb uses 75 W each second?
6. If a 75.0 kg man ran up a flight of stairs 2.50 m high in 1.75 seconds, how many horsepower did he put out? One horsepower equals 746 W.
7. What are the two things that determine moment of inertia?
8. What is needed to cause angular acceleration?
9. Why does a spinning figure skater spin faster when she pulls in her arms?
10. Add 1000 J of energy to an electric motor. If the motor is able to do 850 J of useful work, what is its efficiency?
11. What is the rotational equivalent of force?
12. What is the rotational equivalent of mass?
13. What is the rotational equivalent of velocity?