Physical Science 101 Name_____________



Sample Quiz 6


  1. One meter stick has masses fastened at the ends and an identical meter stick has masses fastened close to the center. Which meter stick has the larger rotational inertia? If the second ruler had very large masses fastened close to the center could you determine from the information given which ruler has the larger rotational inertia? Explain.

  3. Using the ideas of torque and center of gravity, explain why a ball rolls down a hill.

  5. Consider a can of ice and an identical can of water rolling down an incline. Which has the larger torque? Which has the larger rotational inertial? Which will win the race?

  7. Discuss the similarities between Newton's second law for rotation and his second law for linear motion.

  9. Using the ideas of torque, explain why door knobs are at the end of a door instead of in the middle of the door. Comment on how you should open a door in a short period of time with the least amount of force.

  11. A physics instructor throws a model of a carbon monoxide molecule into the air. Describe the center of mass motion of the molecule. How does one of the atoms in the model move with respect to the center of mass?

  13. The occupant inside a future rotating space habitat feels that she is being pulled by artificial gravity against the outer wall of the habitat (which becomes the "floor"). Explain what is going on in terms of Newton's laws and centripetal force. (This is exercise 41 in Chap. 7).

  15. Explain the law of conservation of angular momentum. Give an example how this law might be used.

  17. Hanging from one end of a light (i.e. ignore the mass) meter stick is a 1-kg mass and hanging from the other end is a 3-kg mass. Where is the center of mass of this system? How does your answer relate to torque? (This is problem 1 in Chap. 7).

  19. Explain why a person sitting on a stool who is holding a spinning wheel begins rotating when she flips the wheel over. Which direction will she rotate? Why?