00:04
Okay, so this problem wants us to do a few things here.
00:10
So one thing that it's asking us to do with this wave is to find the amplitude of the wave.
00:16
What we see here is a wave function basically that shows basically the vertical height of this wave in meters as a function of the distance that this wave is traveling horizontally.
00:35
So what we can do is define the amplitude pretty easily about what it is.
00:41
The amplitude is the maximum distance that the wave goes vertically on this graph.
00:49
So the amplitude, in other words, would be the distance maximally that the wave goes up or the distance maximally if the wave goes down from this x -axis.
01:00
We call this the equilibrium axis or point.
01:05
Point of equilibrium.
01:07
And so the amplitude, so part a, the amplitude a is equal to one.
01:22
So it would be one meter would be the amplitude.
01:27
And this could be a plus or minus one meter.
01:33
But it's, you could just say plus or minus one meter.
01:37
I usually just say the magnitude of it is just one meter.
01:42
B is asking us to find the wavelength of the wave.
01:47
The wavelength of the wave is going to be the distance that it takes to complete one cycle of the wave.
01:55
So when we look at the wave and what they've given us, we can see that what we have is if we start right here at zero, and we go along the wave until we get back to the same point.
02:16
All right.
02:18
So here is the same point because the next, if this wave kept going, we would continue to go up again, which is what's happening here.
02:29
So that being said, what we get here for the wavelength, and it looks like what these values are.
02:39
See if i can get through that point there.
02:44
So the values look like they are in every half integer.
02:52
So 0 .51 meter, 1 .52, and then 3, 4, 5, 6 .6.
03:00
So this would be 6 .5.
03:03
And if i look real closely, i can see that that's probably halfway between 6 .5 and 6.
03:09
So the wavelength, as i see it on the graph, is 6 .25 meters.
03:20
Next, it's asking us for the wave speed.
03:24
So wave speed can be found by using the wave speed formula.
03:30
Velocity of a wave is equal to the frequency of a wave times the wavelength of a wave.
03:39
So we have those.
03:40
We have that the frequency is 120 hertz.
03:44
And the velocity of the wave, i'm sorry, the wavelength of the wave is 6 .25 meters.
03:56
So then the velocity should be, after we do the multiplication, should give us 750 meters per second.
04:08
Let's see if i can box some of these...