00:01
In this situation we have a beam that is connected here to a pivot here and a rolling thing here and it has some forces on it.
00:13
So they ask us to do various things.
00:15
In a, they want to replace the supports in a and b.
00:21
This is point a.
00:23
This is point b right here.
00:26
They want to replace it with forces.
00:28
So because this one is a roller b is a roller, it can only do a force that is perpendicular to the surface.
00:35
So it's going to be a reaction, and you call it reaction in b.
00:39
And it's only going to be, it's going to be vertical.
00:43
On the other hand, in a, because this is fixed, but it can rotate, we're going to have a reaction that will have two components, a reaction in y and a reaction in x.
00:55
Of course, the two of them together make the entire reaction on a and b.
01:01
So after that, we need to draw the free body diagram but the free body diagram is basic what we have now with the forces on the object.
01:11
Only thing we need to add is the acceleration is zero because this is a static situation.
01:18
So that will be the free body diagram of the beam.
01:21
We only need to erase the roller and this but that's the free body diagram.
01:30
So in c they ask us to write the equilibrium equations...