00:01
So in this problem, we have this motion diagram.
00:03
So we have our object going through at a certain horizontal place, and then it starts to go downward.
00:16
Let's move that a bit.
00:18
Say somewhere there, there, and we have the velocity vectors already given, and we want to add the acceleration vectors.
00:37
So first we need to know what a motion diagram is, and we see that we have each of these images here, and they should be separated by a constant time step.
00:46
So between these two points, we have some delta t, and that is the same for everyone.
00:55
So if we already have the velocity in green, then we can find what the acceleration is.
01:02
And we know that acceleration is the change in velocity, or the change in time, i guess here in vector.
01:10
So define the acceleration, we want to compare the velocity from the previous point and the current to then see what the acceleration is.
01:18
So for the first point, we can't really define acceleration because we don't know what happened before.
01:24
For the second point, though, we kind of see that the velocity is about the same, and of course, in the picture it is the same.
01:31
So we have no acceleration for these points where it's going horizontally.
01:34
But once we reach our point here, we see that the object starts to go downwards.
01:47
And so forth, we have an extra velocity downwards.
01:53
Because imagine the change in velocity if we take these two vectors and move them to add them.
01:58
We have an extra bit here, which is our change in velocity.
02:06
And then in that same direction will be acceleration.
02:09
If we take our equation here, we can say it also.
02:13
So that the change in velocity is equal to the acceleration times delta t, which tells us that our change of velocity and acceleration are parallel to each other, just differing by the factor delta t.
02:31
So for our point here, we have an acceleration downwards, and that is true for all of these because the difference continues to grow.
02:44
Now if we look at the change in exposition, we see that it is increasing.
02:51
And this is an indicative of an object in free fall.
02:57
If you've looked at two -dimensional motion, which you should have by doing this problem, you'll see that, say, a ball thrown in the air traces an arc, where at the top we have a very small change in distance, but then it increases over time in terms of like the wide distance here.
03:16
And so that's what we can see happening here.
03:20
Through the first interval, the object's in constant motion, b equals constant, and then it begins accelerating downwards with some acceleration, which is probably constant.
03:33
It's hard to tell exactly from the diagram, but it very likely is...