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Acceleration with inclined ramp (Frictionless)

  1. Sep 7, 2008 #1
    1. What is the acceleration of a skateboard down a ramp inclined at 19.5 degrees to the horizontal?

    3.271 is the answer.

    2. I know g Sin[tex]\vartheta [/tex] is the equation to get it, but I don't get why it isn't g divided by Sin[tex]\vartheta [/tex]

    3. In my head I thought the picture was like this: 2wew8bq.jpg

    I know this should be something super easy, so please explain. haha
  2. jcsd
  3. Sep 7, 2008 #2
    g sin theta gives you the component of the acceleration of gravity along the incline.
    g/sin theta would give you a number larger than 9.81m/s^2 which would make absolutely no sense.
  4. Sep 7, 2008 #3
    Right, but the first statement still confuses me. Is there a picture you could go by for this?
  5. Sep 7, 2008 #4
    This should help you

    http://img145.imageshack.us/img145/6905/accelerationvectorgh9.jpg [Broken]
    Last edited by a moderator: May 3, 2017
  6. Sep 8, 2008 #5
    Okay, that totally makes sense now. Thanks! :)
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