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Vibration/Centrifugal Force Question

  1. Nov 2, 2014 #1

    I am making a vibration project which requires me to mount eccentric weights on both sides of an electric motor. I must submit the "generated force(in Kg)" by this motor.

    The RPM of motor = 1000
    Total weight on both sides of the motor = 16.8Kg (8.4Kg on both sides)
    The radius(distance from the center of the shaft to the end of the weight) = 103 mm

    What will be creation of Centrifugal force when this motor is run at 1000 RPM ??

  2. jcsd
  3. Nov 2, 2014 #2
    Where are you going to locate these weights? At what radius?

    Think about the problem of tension in a string holding a rock and being swung in a circle. Your problem is similar.
  4. Nov 2, 2014 #3


    Staff: Mentor

    This doesn't make sense. "Generated force" is measured in newtons, not kilograms.
  5. Nov 2, 2014 #4
    Dale, it does if you work in the bastard (old) metric system that measured forces in kilograms. This is exactly analogous to measuring mass in pounds. I certainly don't recommend this, but I have to recognize it when I see it happening.
  6. Nov 2, 2014 #5


    Staff: Mentor

    So is a "1 kg force" equal to 1 N or 9.8 N?
  7. Nov 2, 2014 #6
    Dale, it is the later, 1 kgf = 9.807 N.
  8. Nov 2, 2014 #7
    Dale, there is also the perhaps more common gram-force, such that 1 gf = 980.7 dynes.
  9. Nov 3, 2014 #8

    take a look at this video. The motor has to be used like this. To vibrate certain appratus

    also look at this image for weight placement

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