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Hi Steve,

do you know or, can you tell me where I can find out the frequency range of a moving car, car radio, fan-belt, etc? I am looking through some sonograms taken by a bat detector that's been positioned on the car and just want to find out which sounds are the car by finding out what the frequency ranges are and how they would look visually?

Any help or advice would be much appreciated

Best Regards


Sonograms are not taken by a bat detector, it has no imaging properties.  For these mechanical parts you mention, the range of frequency in sound emission is absolutely enormous.  If you record and replay you might get a match, but there's no way to match it without a frequency spectrum to match it to from the original.  It's kind of like finding the murder weapon, you have to do that before you can match the ballistics on a bullet to the weapon itself.


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Dr. Stephen O. Nelson


I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.


I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

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