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Homework Help: Torque and equilibrium problem

  1. Nov 2, 2008 #1
    1. The problem statement, all variables and given/known data
    for the 1m long, 5N beam below, find the balancing mass m and the supporting tension T

    ----- ^
    | | | ------
    | m | |(25cm) | 2kg |

    2. Relevant equations


    torque= Fxr
    cross product, F x rsinx

    3. The attempt at a solution

    first i summed the forces

    Fx=0, no forces acting in x.


    forces acting

    1. m1g= 9.8m1
    2> m2g= 19.6N
    3. CG= 5n
    4. T =?

    9.8m1 + 19.6N + 5N - T= 0

    so T = 9.8m1 + 24.6N

    next I summed the torques

    19.6N * 0.75m + 5 * 0.25 -(9.8)(.25m)m1 = 0

    m1 = 6.5kg

    Fm1= 63.7N

    the actual answer of the force is -88.7N, and the T=8.45

    seeing how i have the wrong force values i know that my T will be wrong using it. if anyone can show me where I went wrong in this one that would be very helpful thanks.

    Attached Files:

  2. jcsd
  3. Nov 2, 2008 #2
    sorry about picture, i just uploaded a paint file so hopefuly that works.
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