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Necessary torque required?

  1. Dec 28, 2011 #1
    Hi, I'm new to this forum so I'm not exactly sure if I'm posting in the right place. But I have a question about torque.

    Okay so, how much torque would a motor need to supply to be able to spin a disk with a mass of 54.3 g at 30,000 RPM?

    If you could also provide and explain the formula for determining torque that would be great.

    Last edited: Dec 28, 2011
  2. jcsd
  3. Dec 28, 2011 #2


    User Avatar

    Staff: Mentor

    Welcome to the PF.

    What is the context of the question? It takes no torque to spin a disk on frictionless bearings at a constant RPM. The torque would be needed to spin the disk up from zero to final speed, and to overcome bearing friction and any air resistance involved.

    Also you need units on the mass that you supplied...
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