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Loading reaction with shear and bending moment diagrams

  1. Dec 18, 2009 #1
    a motor vehicle has a wheel base of 3m. four posta ramp with two wheels each side. ramps front wheels have 6kn and rear 8kn. determine the reaction of the supports on the beam?

    vehicle is raised 2.25 m vertically this is done in 45 seconds calculate power of electric motor required use assumptions and a single phase motor running at 3000rpm is used for the task what torque output is required from motor.? sorri for fuzzy diagram bad camera fone

    i worked out correct me if im wrong using a example i have (1.5 x 8) + (4.5 x 9.8 ) = 56.1 Divided by 4 equals 14.025KN. i have no idea where to go from here

    Attached Files:

  2. jcsd
  3. Dec 18, 2009 #2
    Please explain the basis of the equation. I can see that 1.5x8 is possibly taking moments about RH support, but I cannot reconcile 4.5x9.8 with that. In any case, if you want reactions, you can get them by taking moments. An engineer wanting an assurance that the answer is correct might take moments about two separate points, and then solve the two simultaneous equations, and then use sum loads = sum reactions as a check.
  4. Dec 18, 2009 #3
    the 4.5 is the total length like i had in my worked example. but i didnt no where the 9.8 came from in my example so i thought it was a generic number
  5. Dec 19, 2009 #4
    To answer the first part of the question, state the equations of static equilibrium, and then apply them to this case. Have you revealed the whole question? Is the weight of the beam itself significant?
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