00:02
In this example, i'm going to be looking at adding force vectors.
00:07
Okay, so what we have is two force factors acting at this point here.
00:13
All right.
00:13
I have force p and force q.
00:17
And what i want to do is find the resultant of these two forces.
00:21
So i want to find there's some.
00:23
Okay.
00:24
And i have force p equals 60 pounds.
00:31
And i have theta p.
00:32
That's the angle that force p makes with the vertical direction that equals 20 degrees and i have force q force q equals 32 pounds and theta q let's just give it a little q equals 35 degrees and again that's relative to the y axis here all right and i want to find the sum of vector p, force vector p plus force vector q.
01:09
Right and the problem wants us to do this using the parallelogram law.
01:14
So what that says is that when we have these two forces acting at the same point here we have p and q.
01:27
All right we're going to take force q we could do it for force p as well but i'm going to use the example of force q we move it down here instead keeping the angle and the length the same.
01:41
And then we're going to find this leg of this triangle here, and that will be our resultant force.
01:47
And we can see if i had decided to move force p instead.
01:51
We would have taken force p from here and put it down here.
01:55
We can see that we'll have this same vertical component there.
02:00
Right.
02:01
So let's break down our p &q vectors into their components, and we can add them up, and that will give me this leg here.
02:07
All right, so force p we said was, and i'm going to write this in vector form, equals 60 pounds times.
02:20
Let's see, my x component is going to be the negative sign of that 20 degree angle.
02:27
My y component is going to be the negative cosine of that 20 degrees.
02:33
Negative sign 20x minus cosine.
02:43
20y.
02:46
My force q equals 32 pounds.
02:52
And i forgot the units here.
02:54
That's in pounds times.
02:56
Let's go back to our diagram...