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Homework Help: Rotation and Gravitation

  1. Feb 23, 2005 #1
    You have one screwdriver with a thick handle and one with a thin handle. Which one would be better for opening a stubborn can of paint?

    my answer: either screwdriver--they are the same

    Which screwdriver would be better for turning a stubborn screw?

    my answer: the thick handled screw driver

    What force keeps the moon in orbit around the earth?
    Choices: a.)centripetal force b.)gravitational force. c)both a and b
    my answer: c) both a and b

    You turn a corner in your car and slide to the outside edge of the seat. Why does this happen?
    my answer: centrifugal force pulls you to the outside.

    can someone explain the difference between centripetal and centrifugal forces please?

    thank you,

    mark

    EDIT: one mor question

    a coin stays on a turntable because of friction. Part of the friction causes cicular motion. Which direction does the friction point?
    Choices: a) foward along the coin's path. b)towards the center of the turntable. c)away from the center of the turntable. d)backward along hte coin's path

    my answer:..im not quite sure..could someone explain this to me
     
    Last edited: Feb 23, 2005
  2. jcsd
  3. Feb 24, 2005 #2

    Andrew Mason

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    Science Advisor
    Homework Helper

    Since gravity provides the centripetal acceleration, there is only one force. Gravity. a).

     
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