00:01
In this problem, we're given acceleration at initial velocity values in a written form, but we can write them down in a vector form to make things easier.
00:10
Now we want to find the vector notation of the final velocity when this motion reaches its highest y coordinate.
00:22
So let's make a quick plot to see how y against time would look like to see what we're trying to find.
00:30
We can see that over here we have a negative acceleration and we start with a positive velocity in the y -axis so we are going to have a parabola like this where we first have some positive velocity but with the accelerate the accelerate until we reach this point where we have the maximum y value and at the same time our velocity in the y -axis is zero so we so now we know that the velocity in the y -axis is going to be zero.
01:08
What about in the x -axis? because we keep accelerating in a positive direction with an initial positive velocity.
01:18
So we have to find that.
01:20
Now we remember that the equation for a final velocity is equal to the initial velocity plus the acceleration times the time.
01:30
We know the acceleration, we know the initial velocity, but we don't know the time.
01:35
So let's find that first.
01:38
We can find that value by using the following equation...