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Resistance of the tongue.

  1. Jun 28, 2010 #1
    I recenlty bought a very cheap multimeter for $10.

    I switched the multimeter to ohms 2000k and stuck the probes on my tongue. The initial value was 400k and rapidly increased until it exceeded 2000k for which my multimeter cannot read.

    Then I dried the tip of my tongue completely and probed it again. Now the readings increase much slower and sometimes even drop at certain stages.

    My quesiton
    1. Why is the resistance not constant? I read it should be stable at 50k
    2. And why my otngue is dry why is the rate of resistance slower?

    Is something wrong with the MM?
  2. jcsd
  3. Jun 28, 2010 #2
    If your aim is to check the working of your multimeter, why can't you measure a known resistance and cross check the values. Why i am saying this is, one cannot be sure about resistance of tongue or any thing like that.
    Last edited: Jun 28, 2010
  4. Jun 28, 2010 #3
    I suspect that maybe once your hair was all standing perfectly straight up, the resistance started to stabilize. Depending on how much hair gel you use, the 2nd time you tried, it was already standing up so it didn't vary as much. You might just have to try a higher voltage. Perhaps using a the 2 wires from an outlet? :)

    Sorry ... couldn't resist. :) It was just funny hearing about sticking electrical wires on your tongue. I agree with n.karthick that your tongue is not a stable resistor. How well it conducts completely depends on how wet/dry it is plus how hard you push the wires onto it and I imagine even the shape of it could affect it (which changes from moment to moment).
  5. Jun 28, 2010 #4
    Saliva is acid.
    When you stick metal in acid all sorts of interesting electrochemical things happen. It depends on what the metal is and what the acid is and it's concentration plus any other currents and voltages that might be in the circuit (The battery in your meter.)

    Try tasting the terminals of a small battery (and I mean SMALL)
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