00:02
Consider a weight this plate, or tangular plate that is being supported with a ball and socket joint at point a and a roller pin at point b and a tension string along cd parallel to the z axis.
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On our plate we have a uniform leadership load, which has a magnitude of 60 pounds per feet.
00:47
And we have a couple moments being applied of 100 pounds per feet.
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So we're going to want to write our equations for equilibrium, which will involve summing our forces equal to zero and our moment equal to zero.
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But first, let's determine.
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Oh, excuse me, moment is pounds times weight.
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So first, let's determine the total weight.
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W applied to our plate.
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So small caps is the distributed load and capital w is the total load.
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So we have 60 pounds per feet over a distance of 5 feet, so 300 pounds.
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Because the uniform distribution, we could assume it is being applied at midway through the beam.
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Now let's draw the remaining of our forces.
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So here we have our upward tension force.
01:58
We have, in theory we could have three reaction forces for a because it's a ball and a socket joint, but there are no other horizontal forces.
02:07
When i mean horizontal, we'll be along the x -y plane, so there will be nothing to equal amount, so they have to be equal to zero.
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So we have a -y and a -z, x equal to zero, and we're looking for a -z.
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Similarly, we want to find b -z.
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And b -z because the roller pin, it only had one reaction force to begin with.
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So now let's look at our conditions for it.
02:31
The sum of the forces along z multiple to zero, which means that a z plus b z is equal to 300 pounds.
02:50
To the couple of these two forces, we're going to need, oh excuse me, i forgot tangent force.
02:58
Tension force, c...