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Homework Help: Potential Energy and maximum velocity

  1. Feb 18, 2008 #1
    1. The problem statement, all variables and given/known data

    The mass 0.40 kg is released and slides down the incline. The maximum velocity ( taken the instant before the mass reaches the bottom of the incline ) is 1.00 m/s. What is the kinetic energy at that time? What percentage of the potential energy of the system is not converted into kinetic energy due to friction? (converted into heat instead)

    My question is with part b, and the percentage of potential energy lost due to friction.

    2. Relevant equations


    3. The attempt at a solution

    The answer to question a, which is the amount of Kinetic Energy was 0.2 Joules.

    However, I had no idea how to start part b.

    Any help is appreciated, thanks!
  2. jcsd
  3. Feb 18, 2008 #2
    Bumperooski. I tried dividing the amount of PE by KE, and vice versa, but that didn't work. Still lost :/
  4. Feb 18, 2008 #3
    Is that all the info given?
    Do they give any more info about the incline?
  5. Feb 19, 2008 #4
    the hypotenuse of the triangle is 40 cm with the vertical portion at 7 cm.
  6. Feb 19, 2008 #5
    I assume funky is working the same problem then?
    Well, if you know the height, you can find the potential energy. And you know the final velocity, so you know the kinetic energy.
    Now if all your potential energy didn't get converted to kinetic where did it go?
    If you are having problems with just the percent part, the equation is KE/H * 100%
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