00:01
In this example, we're going to be looking at the relationships between position, time, and velocity.
00:09
And we're going to do a little bit of extrapolating data from a graph.
00:13
So let's look at our graph.
00:17
All right.
00:17
And the first thing we want to do is try to describe the motion of the object here that's represented on the graph.
00:24
So we have some object and it starts at the origin.
00:28
So it starts at x equals zero, y equals zero.
00:35
Right, so time equals zero.
00:36
When time equals zero, our y -axis value equals zero.
00:41
So we're starting at, let's just say, grounds level.
00:46
All right, and we see as time increases, our y value increases, until we get to approximately a time of, let's see, call that seven seconds, that b.
01:03
All right, and then our y value starts to decrease.
01:07
All right.
01:11
So what this is saying is that we're looking at an object that has a positive velocity.
01:18
We know velocity is just the slope of the tangent line of a curve.
01:23
So i'll just use this as a quick example.
01:26
So the slope we can see is positive.
01:28
X is positive, y is positive.
01:30
So as x increases, y increases.
01:33
So it has a positive velocity, it flows down gradually, comes to a stop, and then starts to move with a negative velocity.
01:42
You can see that again.
01:43
This slope now is negative.
01:46
So as x increases y is decreasing.
01:52
Right.
01:52
So what this is describing, just for an example, is say you throw a ball straight up in the air, right? you throw it up with some initial velocity.
01:59
It moves in an upward direction.
02:01
Eventually comes to a stop and returns back.
02:03
Down to the ground.
02:06
And there's other examples i can use, but that's the simplest one...