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Electric Shavers Rot Your Brain
Damek writes "According to UW researchers, prolonged exposure to low-level magnetic fields, similar to those emitted by such common household devices as blow dryers, electric blankets and razors, can damage brain cell DNA. The damage appears to be cumulative, so you'd best get rid of your electric razors & blankets ASAP! The full study is available online now. No word yet for Cell Phone users' brains..."
Because all magnetic fields are dipole fields at best, the field drops with the cube of distance, not the square of distance. So, it is even harder to get that field into your skull.
This is because there is no such thing as a "magnetic charge" like there is for electric charge.
(note to pedants: magnetic monopoles are too exotic to comment on, assuming they exist.)
My amazing wife - Artist, Author, Philosopher - Laurie M
Well, you might be surprised as how easily magnetic waves can propagate through materials.
Don't you mean a magnetic field?
How do you think 802.11 works through walls? Or cell phones? etc....
Those are high-frequency electromagnetic (far field) problems. This article refers to low-frequency mahnetic fields. Magnetic fields have much reduced range, so to be in their area of effect you really would have to hold the thing up against your skull.
Man is the animal that laughs.
And occasionally whores for Karma.
It is not a static magnetic field. A 60 Hz magnetic field is also a 60 Hz electric field. The radiation field from a dipole drops of with the inverse of distance squared. The intensity drops off with the fourth power.
It has been a few years since I studied this material. Please let me know if I am in error.
I believe you are. It's quadripole fields that fall off with inverse fourth.
Dipole fields fall off with the inverse cube, as I recall. Inverse square for the individual poles, pluse an extra inverse first-power for the separation between the poles. (Quadripole fields get an extra inverse first-power for the separation for their component dipoles in the other dimension.)
Let's assume for now that the leakage from the motor is mostly a dipole field. (CAN'T be a monopole. B-) ) For a DC field, or the "near field" of an AC field, the dipole field dominates - and it falls off inverse cube. Get two inches from the shaver and the field is 1/8th what it was at one inch. Four inches makes it 1/64th, and so on. Falls off REALLY fast with distance.
As you get farther out the changing magnetic field creates a changing electric field that in turn supports the changing magnetic field (as long as they're both propagating at lightspeed). Then you have an electromagnetic wave, detached from its launcher. This falls off with inverse square.
Under a quarter wavelength the near-field is so dominant you can pretty much ignore the far-field. Over a wavelenghth or so away the situation is reversed (unless your driving element is large compared to a quarter wavelength).
So what's the wavelength of 60 HZ? About three thousand miles.
I don't think we need to worry about the far field. B-)
So figure inverse cube falloff - or faster if the motor's magnetic leakage has more than two poles.
(This is why you need to get REALLY CLOSE to a magnet to erase your credit cards.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
ok... its important to remember our history... Lai and Singh are the same two MORONS who made similar claims about magnetic fields almost ten years ago:
http://www.electric-words.com/cell/research/laisin gh/memory1.html
and NOBODY was able to duplicate their results. Although the two made $10,000 a pop being 'expert witnesses' for people who brough lawsuits against Motorola et. al. claiming their cell phones gave them tumors. It looks like they must have ran out of money.
This is the WORST kind of junk science imaginable.
It was a University of Washington study. The website is just reporting the results.