Electronics/Urban Legends

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Various legends and their status as true or false.

1. Touching both ends of a 12 Volt car battery will kill me. False. The human body has millions of ohms of resistance so unless you are wet or are bleeding you should be ok. Millions of ohms of resistance means that the amount of current flowing will be astronomically small.

2. Cell phones cause cancer or brain damage. Probably false. A cell phone operates at 900 MHz and 3GHz. Visible light has a frequency of 1 Petillion 10^15 Hz. Just below that is UV where you get sunburns. That's a million times the frequency. So if cell phones hurt you than what must visible light be doing to you? If you believe it will hurt you than your only hope is to live in darkness inside a Faraday cage like a CHUD. No microwave, infared, or visible light for you.

3. One time a cell phone caused a fire at a gas station.

4. CRTs are bad for you and expose you to x-rays. False, there are some x rays that get through occasionally, but not frequently enough to cause real damage.