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Math Help - Center of the Circle Path

  1. #1
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    Center of the Circle Path

    If a circle of radius 2 is made to roll along the x-axis, what is an equation for the path of the center of the circle?
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  2. #2
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    Does it seem reasonable to you that the radius of a circle remains constant?
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  3. #3
    MHF Contributor Quick's Avatar
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    Sorry, your Web browser is not Java compatible. This prototype will not be of much interest to you.


    A good question


    Move the red point to see the "shape" it makes.









    You really should have been able to do this in your head.
    Q_{u^{i_{c^k}}}
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  4. #4
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    ok

    I'm sorry but your answers do not make sense.

    Can you help me?
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  5. #5
    Forum Admin topsquark's Avatar
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    Quote Originally Posted by symmetry View Post
    I'm sorry but your answers do not make sense.

    Can you help me?
    As the circle rolls there is always a distance equal to the radius between the edge of the circle and the center. So what is the position of the center of the circle as it rolls on a horizontal surface?

    Hint: The answer is in the statement above. If you aren't seeing it, you are thinking about the problem too hard. If it helps, take a can and roll it on a table and see what the center of the can does.

    -Dan
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  6. #6
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    Quote Originally Posted by symmetry View Post
    I'm sorry but your answers do not make sense.

    Can you help me?
    I thought the diagram made it pretty clear

    Did you try moving the red point (just click and drag, and the circle will roll across the "table")
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  7. #7
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    ok

    Dan,

    I guess the answer is right in the question.

    Thanks!
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    Forum Admin topsquark's Avatar
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    Quote Originally Posted by symmetry View Post
    Dan,

    I guess the answer is right in the question.

    Thanks!
    I want to make sure you've got it. What is your equation for the center of the circle?

    -Dan
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  9. #9
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    ok

    Thank you all for your replies.

    To Quick:

    Your diagram never appeared with in the reply.

    To Dan:

    The equation is y = 2 because the center of the circle makes no vertical movement, right?
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  10. #10
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    Quote Originally Posted by symmetry View Post

    To Quick:

    Your diagram never appeared with in the reply.
    Can you still not see it?

    What browser are you using?
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  11. #11
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    ok

    I got it and answered my own question thanks to the hints.
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