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Torque and force

  1. Dec 17, 2003 #1
    as you all now torque in rotational motion has similarity with force in translational motion. but torque has the same unit as energy.it seems to me that there is a problem. Any explanation you have? (please ssmt different than " they are defined that way!!"
    Last edited: Dec 17, 2003
  2. jcsd
  3. Dec 17, 2003 #2


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    In translational motion, work done (energy) is

    [tex]E=\int Fdx[/tex]

    In the same manner, in rotational motion,

    [tex]E=\int\tau d\theta[/tex]

    Since [tex]\inline{\theta}[/tex] is dimensionless, torque [tex]\inline{\tau}[/tex] has same units as energy. If it helps in keeping things apart, you can think of the units of torque as being say joules per radian.
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