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Homework Help: A mechanics problem involving a large gear and a small gear

  1. May 29, 2012 #1
    1. The problem statement, all variables and given/known data

    in the system of gears the larger gear of radius 1m and mass of 2kg is about to mesh with the smaller stationary gear of radius 0.5m and mass 1kg at the instant of meshing the speed of a point on the circumference of the larger gear is 50m/s both gears are free from the moment of meshing.
    neglecting friction what is the angular velocity in radians per seconds of the larger gear after engagement.

    (there are no teeth on the gears, clockwise rotation is taken positive)

    2. Relevant equations

    there are 5 possible answers (80,40,39,20,10) i think it is 40

    3. The attempt at a solution

    i think that you need to use conservation of angular momentum or energy
    Iω= angular moment (I is inertia)

    ke=1/2 Iω^2
  2. jcsd
  3. May 29, 2012 #2


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    Staff: Mentor

    A guess is not an attempt. Can you justify your guess with some calculations?
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