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Homework Help: Conservation of Energy Questions

  1. Mar 27, 2007 #1
    Question #1

    A ball of mass 0.5 kg is tossed upward into the air. When it leaves your hand, it has a kinetic energy of 138 Joules. Use conservation of energy to find how high it goes. (Ignore air resistance)

    Question #2

    A roller coaster car with a mass of 265.3 kg starts from a height of 114.9 meters above the ground just before rolling down the frictionless track. Using conservation of energy, find the speed of the car just as it reaches the ground.

    After the car reaches the ground, it travels horizontally on the track, where a frictional force of 999.6 Newtons slows the car to a stop. What is the work done on the car in bringing it to rest?

    How far will the car go before it comes to rest?

    I don't have a clue what I am doing, I SUCK at physics! Thanks for the help!
  2. jcsd
  3. Mar 27, 2007 #2


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    Homework Helper

    Well, you probably have some equations you're familiar with?
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