Minuscule changes in the squeezing of the sensor trigger far larger changes in the flow of electrons, which makes the sensor extremely sensitive.

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Arch your tongue so that the liquid will flow over every flavor sensor in your mouth, including the soft palate.

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When you set a bottle down under the spigot, an infrared sensor automatically turns on the flow.

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The trick is to find a way to make this flow rate change when the chemical that the sensor has been designed to detect is present.

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