B2-34: EQUILIBRIUM OF TORQUES - ANGLE BRACKET

  • ID Code: B2-34
  • Purpose: Verify the equation for torques when the center of mass is outside the object
  • Description:

    A bracket is bent into a right triangle with arms of length a and 2a, and suspended from the end of the small arm as photographed. What is the angle of repose r of the small arm with the vertical, at equilibrium?


    From the equation of torques, w1 x1 = w2 x2,


    where: w1= mg and x1= a/2 sin r,


    also: w2 = 2mg and x2 = a cos r - a sin r)


    From these, tan r = 4/5, and r = 38.66 degrees.
  • Availability: Available
  • References: http://lecdem.physics.umd.edu/images/refs/refsb.htm#B2-34
  • Loc codes: B2

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