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Accelerometer via ball on string

  1. Jul 7, 2005 #1
    How would I go about measuring forward acceleration using a free-swinging ball on a stand? Could anyone post a free body diagram or an equation that might describe this?
  2. jcsd
  3. Jul 7, 2005 #2


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    Two external forces on the ball:
    downward gravitational force with magnitude (mg)
    tension tangent to the the rope (T)

    Compute net-force vectorially.

    Use Netwon II.
    Solve for the acceleration (a) as a function of angle (theta) with respect to the vertical.
  4. Jul 7, 2005 #3
    Would tan(theta)=a/g ?
  5. Jul 7, 2005 #4

    Doc Al

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    That's right. (Where theta is the angle the string makes with the vertical.)
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