00:02
Okay, so from the problem statement, we know that this ferris wheel is rotating at a constant speed of 4 .5 radiance per minute.
00:17
The radius of this ferris wheel is 25 feet.
00:25
And then if we draw this ferris wheel, you know it has some legs here, and it's saying that the center of this ferris wheel is 31 feet above the ground.
00:39
At first, we want to write an expression to represent the number of radians.
00:46
Looks like you've gotten this one right.
00:52
For a, the number of radians is 4 .5 radians per minute times t minutes.
01:07
For b, we want to know how long it takes for nick to complete one full revolution.
01:12
Well, we know that there are two pi radians in one revolution.
01:16
So it's going to be two pi radians per revolution divided by 4 .5.
01:28
Radiance per minute.
01:32
When we flip and multiply, oops, draw that line there.
01:39
When we flip and multiply this, these units radians are going to cancel and we're going to get 2 pi over 4 .5 minutes per revolution.
02:04
Okay, let's clear up some space right here for c.
02:14
We want to know in terms of t, what is nick's height above the center of the ferris wheel.
02:25
Well, the ferris wheel has a radius of 25 feet.
02:29
So we know that this is going to be 25.
02:34
The height is going to be the y coordinate around the circle.
02:37
We know that that y coordinate is modeled by the sign function.
02:43
And then we need to figure out what the period of this sign function is...