Speed of Sound in water given frequency

[jdg]

A 190 Hz sound traveling in fresh water has speed of?
I'm not sure which equations to use, or where to start. I tried wavelength = V/f , with V being constant, 1493 m/sAny help would be greatly appreciated!

 

[jgens]

Are you trying to find the speed or the wavelength in this problem (the question indicates speed while your work indicates wavelength)? If the question is about speed, what do you know about the speed of a wave through a particular medium? If the question is about wavelength, what is the relationship between the frequency, wavelength, and speed of a wave?

 

[jdg]

I know it has something to do with the density of the medium, but I'm not sure what the equation is

-the density of fresh water is 1000 kg/m3

 

[jgens]

I'm guessing the question is about the speed of the wave then? Well, just to get you thinking, in air at a constant temperature, what is the difference in speed (if any) between a sound wave with a frequency of 200 Hz and a sound wave with a frequency of 400 Hz?

 

[jdg]

I would think that at a constant temperature the speed would be constant?

 

[jgens]

Correct! So what does this suggest about the pertinence of the frequency of the wave in this problem?

 

[jdg]

the frequency won't change the speed in water?

 

[jgens]

No, it suggests that the speed of the wave doesn't depend on the frequency!

 

[jdg]

so it doesn't matter what the frequency is, the speed of sound remains the same in the water?

 

[jgens]

Yup, assuming that the water is at a constant temperature.

 

[jdg]

so how do I find that speed with the given information?

 

[jgens]

Well, you've already provided a speed of sound in water (you did in the first post)!

 

[Feldoh]

so how do I find that speed with the given information?

Google it. Since you all ready said that the frequency doesn't have anything to do with the actual speed.

 

[HallsofIvy]

You said, in your first post: "wavelength = V/f , with V being constant, 1493 m/s".

If you were trying to find the wavelength, given the frequency, you could use that formula. But you said you were trying to find the speed of sound in water which, as you said, is 1493 m/s!

 

[jdg]

I used the constant, 1493 m/s, which is given in my text for SoS in fresh water, it came out wrong

 

[JazzFusion]

Were you given a value for the bulk modulus of water?