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Homework Help: Rotational motion

  1. Jun 12, 2005 #1
    have a question.
    diameter of a rotor is 7.60m and rotational speed of 450 rev/min. calculate speed of tip. anywell would be welcomed
     
  2. jcsd
  3. Jun 12, 2005 #2

    Pyrrhus

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    What equation relates both?

    [tex] v = \omega r [/tex]
     
  4. Jun 12, 2005 #3
    the answer in the back of the book says179 m/s. but when i try that formula it comes out as 311.6
     
  5. Jun 12, 2005 #4

    Pyrrhus

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    Oh sorry, yes the book is right

    A rev is equal to 2 pi radians, and a minute is equal to 60 second. You need to homogenize (spl?) your units.
     
  6. Jun 12, 2005 #5
    the rev/min is 47.81 rev/sec
     
  7. Jun 12, 2005 #6
    sorry its 47.12 rad/s
     
  8. Jun 12, 2005 #7

    Pyrrhus

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    Multiply it with 3.8 m
     
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