00:01
All right, hello, in this question we are given this information that the speed of a sound wave in air is going to be 340 meters per second and that's equal to the frequency times the wavelength.
00:11
And we're asked various things.
00:12
The first is if we have a frequency of 3400 hertz, what is the wavelength? well, the wavelength is going to be the speed over the frequency.
00:24
And we have both of those, so this is pretty easy, just plug in those values.
00:29
And if we do that, we're going to 1 over 10 or 0 .10 meters there.
00:34
Part two says, the difference in pressure helps us determine the direction of where things are.
00:41
And so let us assume that the most effective shadowed sinusoidal sound pressure waveform is that with a wavelength equal to the diameter of the object producing the shadow.
00:50
So that's a fancy way of saying our most effective wavelength that we're going to have here equals the diameter of whatever our object, our shadow object is.
01:03
Pretend that the head is a round ball with a diameter of 0 .1 meters or one tenth of a meter.
01:08
Using the formula, determine the frequency most effectively shadowed by the head of diameter 0 .1 meter.
01:14
So we want to find the frequency such that our wavelength is the same as our shadow distance or shadow diameter, which in this case is going to be 0 .10 meters.
01:28
Well, we can use the equation above, c equals f times our wavelength, and we can solve for frequency...