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Do you think cell phones pose a health risk?

  1. Jul 24, 2010 #1
    I have a few questions/thoughts about microwaves ovens and cell phones that I'm hoping someone here can help with.
    Microwaves ovens and cell phones both use around the same range of frequencies. But microwave ovens use way more power. Ovens about 500W, cell phones at most 2W. More power would result in higher intensity for a given area. This is why an oven cooks food and cell phones don't. Correct me if I'm wrong.

    I saw a program on tv where they piled a bunch of cell phone on an egg and called them to see if they would cook the egg. It didn't, but they didn't explain why.
    Can blasting an egg with a low power frequency ever equal a high power frequency?
    I know that the photoelectric effect says blasting it with lower frequency photons won't be the same as one high powered photon.

    And some final questions. Do you think cell phones pose a health risk? What about a cell phone jammer that is blasting out multiple frequencies all the time? What about wifi signals that are all around us?
  2. jcsd
  3. Jul 24, 2010 #2


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    Science Advisor

    Re: Microwaves

    What do you think would happen to a cell phone if placed in a 500W oven? I'm pretty sure a pile of cellphones would produce enough power to start damaging each other before significantly heating the egg.

    And just how many cell phones did they have? Even with 20 cell phones you are not getting a 10th of the power of a small microwave oven.
  4. Jul 24, 2010 #3


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    Staff: Mentor

    Re: Microwaves

    Residential ovens are typically 1200 or 1500W. Cell phone power output is variable - it only outputs 2W if the nearest cell tower is having a tough time connecting.
    Assuming all the phones were putting out their peak power, it would take 600 of them to produce the same power as a typical small microwave.

    But the main problem with this approach is that a microwave oven is closed, which makes all of that 1200 watts go into the egg. A pile of cell phones still emits its energy in all directions, so that egg is only going to get a tiny fraction of that energy - probably not even 1%.
    Microwaves interact with water, which causes it to heat up. It doesn't interact the same way with other materials. Different frequencies of radiation will have different interactions with different materials.
    No: There is no credible study showing an apparent risk or any mechanism theoriezed for how they could cause damage.
    Unless you wear them as a hat, they send substantially less radiation through your head than a cell phone does, so no.
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