Midnight Oil

Subject: Re: [powderworks] Re: email warnings about technology, crime, viruses etc
From: RM
Date: 10/01/2008, 10:17 am
To: powderworks@yahoogroups.com.au

[i can't resist!]
you guys have confused this list with slashdot !   :D
ok, seriously, appreciated your interesting notes. caused me to recall now ancient lectures receding from memory.
http://www.google.com.au/search?q=slashdot+microwave+cell+phone
RM

on 10/01/08 09:31 Chris said the following:
The other part of the argument to consider here is wattage. Wattage is a
measure of power, where power is energy over time. The lightbulb in your
microwave may emit, for example, 40 watts of a power, mostly as heat, but
some portion as light. A typical microwave oven may emit 1000 watts in
microwaves. By comparison, a mobile phone emits on the order of 250
milliwatts.

The other factor that makes microwave ovens so efficient is the particular
frequency they work at. 2.4ghz interacts well with (excites) water
molecules. The physics and chemistry behind that is fairly complex, but it's
to do with the fact that electromagnetic fields consist of a changing
electric and changing magnetic field. That changing electric field causes
the water molecules to move (to rotate, actually), and through friction this
is converted to heat.

http://howthingswork.virginia.edu/microwave_ovens.html explains much of this
quite clearly, along with other microwave related physics.

There may be a physicist here on the list that can explain this better than
I, a year 12 student, can. Any corrections are welcome, my intention here
was just to make people think a little bit.

Chris




On Jan 10, 2008 9:37 AM, Fredrik Olson <fredrik@fredrikolson.net> wrote:

>  Hi Chris
>
> Interesting discussion. But I'm not sure I'm buying your argument here.
> Microwaves heat up food much faster than the light from the lamp in the
> microwave oven would heat the food up. This can't be explained by the e=H*f
> formula, as I understand it. Something must be missing? I'm genuinly
> interested, so please don't take me wrong.
>
> Best regards,
> Fredrik
>
>
>
> At 23:20 2008-01-09, you wrote:
>
> Indeed. Thank you for stating it so succinctly, or I might have posted
> something rather more irate.
>
> I'm always scared by how easily people are deceived by things that are
> easily shown to be impossible by an understanding of very basic
> physics. Unfortunately, it seems that what I consider "basic physics"
> wasn't taught 30 years ago, and so many people carry irrational fears
> about (particularly) electricity, computers, microwaves and mobile phones.
>
> In this case, I suspect that the "plausibility" of the story comes
> from a misunderstanding. The inclusion of having to answer the phone
> reminds me of the (true) stores about people being killed by lightning
> strikes being conducted by their phone lines.
>
> If you value your time, there's no need to read further.
>
> While I'm at it, I'd just like to take a commonsense approach to the
> fears of "mobile phone radiation". Yes, I'm well and truly hijacking a
> soapbox here, but this forum is pretty quiet these days anyhow.
>
> Many here may know that mobile phones operate using so-called
> "microwave radiation". The simplified electromagnetic spectrum looks
> as such:
>
> Low Frequency High Frequency
> Radio - Microwave - Infrared - Visible Light - UV - Xray - Gamma
>
> Now for the part that isn't taught until elective physics:
>
> e = hf. That is, Energy of a wave is equal to Planck's constant
> multiplied by the frequency. Since Planck's constant is a constant, we
> can say that energy is directly proportional to frequency.
>
> Thus, we can see why high frequency x-rays and UV light are harmful -
> they carry a large amount of energy. Microwaves, on the other hand,
> being of a low frequency carry less energy than visible light, and
> even than infrared (heat energy). So if you're worried about mobile
> phones cooking your brain, I suggest you don't go outside. The risks
> are far greater.
>
> Sorry about your time!
>
> Chris
>
> --- In powderworks@yahoogroups.com.au <powderworks%40yahoogroups.com.au>,
> RM <m2k7@...> wrote:
> >
> > email warnings about technology, crime, viruses etc are generally all
> > fakes and should be rebutted promptly to stop their travel.
> >
> > if you get any warning, especially any that say "FORWARD THIS TO
> > [everyone in your mail list]", first google a key phrase out of the
> mail
> > (in quotes might help too) and see if it shows up on the regular hoax
> > monitoring sites:
> > eg:
> > I googled : "ever answer a cell phone while it is being RECHARGED"
> > and found:
> > http://urbanlegends.about.com/library/bl_cell_phone_electrocuted.htm
> > http://www.hoax-slayer.com/cell-phone-charging.html
> > http://www.snopes.com/horrors/techno/cellcharge.asp
> > as the top 3 listings. These 3 sites are the regular hoax-busters.
> >
> > most people have seen enough of these to have already built up a sense
> > of loathing for both the mails and those who pass them on, but most
> > people also have to first send one to learn this, so don't feel too
> > embarrassed, we've all been caught.
> >
> > Cheers
> > RM
> >
>
> >
>


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