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Homework Help: I'm need some help

  1. Oct 14, 2004 #1
    i'm not sure how to begin this problem. "a cart that is moving at 8:00m/s heads up a frictionless ramp inclined 10.0 degrees from the horizontal. how far up the ramp should it go?" also i want to know if i'm on the right track with this question "give an example of each of the following objects or systems. a) and object with a negative potential enery. " i said an object at rest. b) " an object with zero kinetic energy" i said a ball stopped in a catchers mitt. c) a system that does mechanical work and loses energy. i said an open , non isolated system. and d) themal energy being produced by a system. i said a can of pop on a beach, fast moving molecules. any help would be great as i'm trying to teach my self. its kind of hard thanks
     
  2. jcsd
  3. Oct 14, 2004 #2

    ek

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    1/2mv^2 = mgsinxd

    1/2v^2 = gsinxd

    d = v^2/2gsinx

    That is one way you can solve it. There is probably more than one way.

    I might have screwed up though, who knows. In fact I probably did. I'm going to try and do it another way.

    Here's another way, easier I guess:

    a = gsinx (it's going up at a ten degree angle, so the component of gravity is gsinx)

    v^2 = 2ad

    d = v^2/2gsinx

    Same thing. Guess I was right after initially screwing up sines and cosines. It happens to the best of us.
     
    Last edited: Oct 14, 2004
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