There are two forces in every simple beam diagram. Vertical loads and moment loads. Think of moment force as the turning force. The moment force at both A and B is 0. This because the beam is free to rotate if there was moment force the beam would spin. Let solve the 2 forces.
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Solve sum (Σ) all the forces in the vertical or y direction(fy). Note the forces in the up direction are positive and the ones down are negative. Force at A is call FyA and Force at B is call FyB Hint: there are two variables so the equation can’t be solved
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Solve the Sum (Σ) of all the moment forces at point A (Ma). This is 0 as stated before ΣMa=0. Moment forces units are measured in load*distance from the point we are measuring. There for we can add all of the forces x distance and find the missing variable.
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Calculate FyA x distance. This will equal 0 and can be ingored
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Calculate the equivalent load of the distributed load. this is weight x length.We then have to find the location of this equivalent load. This happens at the mid point of the distributed load. The force is equivalent weight x distance from A Keep in mind Negative is down.
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Calculate the point load. Weight x distance from point A
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Calculate the fyB. Weight x distance from point A. Keep in mind positive is up.
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Solve for fyB this is the only variable in the equation. because fya =0 and Ma =0.
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solve for fya. fya can be solved using the equation in step 1.
This video may help. Post your steps and or questions below and I check them.
