# Experimentobtaining sound from molecules

1. Jan 2, 2013

### Treacle

Was just wondering whether or not it was at all possible to create "sound" from molecule interactions, and if so how would I go about it?
I was going on the theory that if E=hv then a frequency is obtained when this equation is applied and as sound is theoretically a frequency (movement of particles) .. would it not be possible to slow down and increase 'v' in order to get an audible frequency as 'sound' ?

Is this at all possible-just thinking out loud and wondering

If it was..then how would I go about it?

2. Jan 2, 2013

### CWatters

Not quite what you asked for but....

Any electronic component that's not at absolute zero generates thermal noise.

http://en.wikipedia.org/wiki/Johnsonâ€“Nyquist_noise

http://www.daycounter.com/Calculators/Thermal-Noise-Calculator.phtml

It wouldn't be very interesting to listen to, essentially white noise.

You could build a thermal noise generator that simply amplifies the noise produced by a resistor. High gain is required so several stages of amplification might be necessary instead of trying to do it with a single stage (max gain of an op-amp is limited by it's non-ideal properties - such as DC offset). You would be able to hear those components in the audio range, but obviously not those outside it.

Last edited: Jan 2, 2013
3. Jan 2, 2013

### Drakkith

Staff Emeritus
E=hv tells us that the energy of a photon is equal to the frequency of the EM wave (v) times plancks constant (h). It is not related to the frequency of a sound wave.

4. Jan 2, 2013

### Treacle

I understand that the equation gives the frequency of an EM wave but was thinking about mapping that onto a sound frequency ? Do you think that may work?

5. Jan 2, 2013

### Drakkith

Staff Emeritus
I'm not sure what exactly you are looking for. What does E=hv and molecules have to do with this? Keep in mind we already use EM waves to transfer sound through radio, although the technique is a little different than what you seem to be proposing.

6. Jan 2, 2013

### johnbbahm

A lot of the optical and acoustic wave formulas work the same, except that
in the acoustic world "c" becomes the speed of sound in the medium in question.
Beyond that there in not much overlap. Some of the real long wavelength IR
may produce some secondary sound (popping of a microwave heated object),
but I don't think that is what you are asking.
The two frequency scales may overlap, but are different affects.