What does reversible mean in the context of sensors?

What does reversible mean in the context of sensors?

I have searched for ages and can't find anything!

I have been asked to describe what makes the ideal sensor and that was in the list.

Thanks in advance.

2 Answers

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  • MarkG
    Lv 7
    9 years ago
    Best Answer

    A reversible sensor can respond to an increase or decrease stimulus. Compare to an irreversible sensor that once stimulated cannot return to the less stimulated state.

    Consider an egg as a G-foce sensor and assume that it will break if subjected to a 3 G force. Drop the egg from a high enough height and it will break and indicate that you have exceeded the 3G limit. You cannot "Un Break" the egg once its broken you cannot reverse its broken state and reset it.

    An old style breathalizer to test for drunk driving used an irreversible chemical reaction to check for the presence of alcohol in your breath. A specific volumen of air was bubbled through a liquid that changed its color in the presence of alcohol. A light was beamed through the liquid and measured by a light detector. At the start of the test the meter was zeroed and the diver blew into a tube and their breath bubbled through the liquid. Any alcohol changed its color and effected how much light could pass through the liquid and would show up as a deflection in the light meter. The test could not be repeated without replacing the chemical reagent liquid Or without rezeroing the meter to compensate for the colr shift from a previous test.

    Now lets consider a reversible sensor such as a resistive humidity sensor. As this sensor is exposed to water its resistance changes. Lets say it becomes less resistive as it is exposed to more humidity )becomes wetter). As a reversible sensor we would then expect to see the opposite happen if we let the sensor dry out by exposing it to air with less humidity. This is exactly what happens the sensor dries out and its resistance rises.

  • Sylvia
    Lv 4
    4 years ago

    Both Ymmo and Frau summed it up. Recons base thier practices and traditions on what WAS, what we KNOW, not what we THINK. An example (no offense to Wiccans) is if someone calls quarters that is NOT recon. Recons will consult 80 books by 60 different folklorist and archeologist, debate it into the ground, come to a conclusion and THEN do it. Any recon will laugh at that because you freaking know I'm right.

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