[PDF]Chapter 6: The Human Auditory and Visual Systems
https://www.princeton.edu/~cuff/ele201/.../human.p...
Princeton University
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The human ear consists of three main components called the external (or outer) ear, the middle ... to higher frequencies, while the other end is more flexible and responds to lower .... light collected by the optical system (namely the eye), etc
https://www.princeton.edu/~cuff/ele201/.../human.p...
The human ear consists of three main components called the external (or outer) ear, the middle ... to higher frequencies, while the other end is more flexible and responds to lower .... light collected by the optical system (namely the eye), etc
Princeton University
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Radio - New World Encyclopedia
www.newworldencyclopedia.org/entry/Radio
Jun 23, 2015 - 1 Radio waves; 2 Radio communications; 3 History ... low frequency (LF): 30–300 kHz; includes long-wave (LW), 153–279 kHz; medium-wave .... FM broadcast radio sends music and voice, with higher fidelity than AM radio.
Sound: Is it possible for radio waves in the frequency range of human hearing to cause resonance within the ear (and perhaps for humans to "hear" some of those frequencies)?
10 Answers
There is overlap of the audio and radio frequency spectra.
The normal human
Hearing range extends from 20 Hz to 20 kHz.
For the relevant part of the Radio spectrum:
But as others have pointed out, radio waves are quite different from the acoustic waves our ears detect. Is it possible that radio waves with frequencies within or near the spectrum of hearing can produce electrical effects within our bodies or mechanical vibrations from the surrounding environment that can be sensed as sound?
Suggestive, but hardly conclusive.
And now we move beyond normal science to what some readers might characterize as fringe science, investigations of "The Hum."
A Mysterious Sound Is Driving People Insane — And Nobody Knows What's Causing It
The normal human
wikipedia.org
For the relevant part of the Radio spectrum:
- Extremely low frequency (ELF) 3–30 Hz, 100,000 km – 10,000 km wavelength: Communication with submarines
- Super low frequency (SLF) 30–300 Hz, 10,000 km – 1000 km wavelength: Communication with submarines
- Ultra low frequency (ULF) 300–3000 Hz, 1000 km – 100 km wavelength: Submarine communication, communication within mines
- Very low frequency (VLF) 3–30 kHz, 100 km – 10 km wavelength: Navigation, time signals, submarine communication, wireless heart rate monitors, geophysics
But as others have pointed out, radio waves are quite different from the acoustic waves our ears detect. Is it possible that radio waves with frequencies within or near the spectrum of hearing can produce electrical effects within our bodies or mechanical vibrations from the surrounding environment that can be sensed as sound?
High-power extremely low frequency RF with electric field levels in the low kV/m range are known to induce perceivable currents within the human body that create an annoying tingling sensation. These currents will typically flow to ground through a body contact surface such as the feet, or arc to ground where the body is well insulated.Source: http://en.wikipedia.org/w
Suggestive, but hardly conclusive.
And now we move beyond normal science to what some readers might characterize as fringe science, investigations of "The Hum."
A Mysterious Sound Is Driving People Insane — And Nobody Knows What's Causing It
So what's behind the Hum? After nearly four decades, Hum investigators may finally have some idea. The general consensus among sufferers is that the Hum is comprised of very low frequency (or 'VLF', in the range of 3 kHz to 30 kHz and wavelengths from 10 to 100 kilometers) or extremely low frequency (or 'ELF', in the range of 3 to 30 Hz, and corresponding wavelengths from 100,000 to 10,000 kilometers) radio waves, which can penetrate buildings and travel over tremendous distances.
It's possible in an indirect way, by stimulating hair near your ears. See this post on the NASA site Astronomy Picture of the Day. http://apod.nasa.gov/apod
A few skygazers even discovered that some bright Leonid fireballs made faint, gentle, hissing sounds(!), a surprising effect only recently appreciated and understood. Accounts of fireball meteors making noise have long been viewed with skepticism, particularly because sounds were reportedly heard just as the meteor was seen overhead. But light travels much faster than sound so, like delayed thunder from a distant lightningstroke, a meteor produced sound should only be heard long after the meteor streak was seen. A sound explanation supported by laboratory tests is that turbulent plasma created by the meteor's passage generates very low frequency radio waves. Traveling at light speed the radio waves reach the ground simultaneously with visible light where they are strong enough to induce oscillating currents and audible vibrations in common objects like grass, leaves, wire-frame glasses, and perhaps even dry, frizzy hair.
No. Ask any ham radio operator or electronics experimenter who's fooled around with "whistlers" - the maximum amplitude is usually in the 3KHz to 5KHz range, well within the human hearing range - but you can't hear them with your ears, you need a receiver built to detect them, because they're electromagnetic radiation, not pressure waves.
Contrary to what everyone says this is not nonsensical question. As everyone pointed out, the ear is sensitive to mechanical energy, not to electromagnetic energy, However, since matter contains charged particles, intense electromagnetic waves could potentially introduce audible mechanical vibrations inside the ear.
Unfortunately I don't have information on how intense an electromagnetic wave needs to be in order to be audible, if it is even possible.
Unfortunately I don't have information on how intense an electromagnetic wave needs to be in order to be audible, if it is even possible.
The ear is sensitive to air pressure, not electromagnetic waves. Air does not react to electromagnetic. But iron does. Get nearby an AM antenna (but not too much nearby), pick a fork, and you'll hear the radio station, as the fork will vibrate with the electromagnetic waves and create air vibrations that our ear can hear.
We "hear" atmospheric vibrations. We "see" electromagnetic radiation. We might have a better chance of seeing radio waves (a form of electromagnetic radiation) than ever hearing them. And by better chance I mean 99.999999999999999999999% chance we'll never ever see them. But technically radio waves do propagate through the medium in which our vision is sensitive. But there is a 100% chance we'll never hear them directly.........we COULD build a machine that transformed radio waves into audible sound waves. Then we could listen to live baseball games and rock n' roll.
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