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Homework Help: Force reactions of balls in a tube

  1. Jan 31, 2015 #1
    1. The problem statement, all variables and given/known data
    Two smooth balls of radius 10[cm] and weight 6[kg] are inside a tube of radius 16[cm] that's on the table. what are the reactions from the walls and what is the minimum mass of the tube to be in equilibrium

    2. Relevant equations
    Disassembling of forces using trigonometry

    3. The attempt at a solution
    The middle triangle is a classic 3-4-5 straight angle triangle multiplied by 15 so the reactions from the walls are 3x15=45. but the reactions are horizontal so at any weight the cylinder stays in place, no?

    Attached Files:

  2. jcsd
  3. Jan 31, 2015 #2
    Aren't the balls exerting a moment on the tube?

  4. Jan 31, 2015 #3
    Last edited: Jan 31, 2015
  5. Jan 31, 2015 #4
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