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Homework Help: Testing thermistor and calibration - sensors

  1. Jan 6, 2004 #1
    Hi please help I have to do a piece of coursework on sensors. I am testing a thermistor and my teacher mentioned something about calibration but I dunno what it is can someone help please. I have taken results for the resistances for every ten degrees from 0 to 150
  2. jcsd
  3. Jan 6, 2004 #2


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    Science Advisor

    Please do not post the same question in different fora.

    To "calibrate" an instrument simply means to determine how the reading of the instrument correspond to actual values of the quantity being measured. For example, if you made your own thermometer by, for example, putting mercury in a thin tube, you would have to determine what height of mercury corresponded to what temperature before you could start. Even instrument that appear to be reporting the value directly need to be calibrated: I got on a scale the other day and, to my amazement it read exactly what I consider to be my ideal weight. Unfortunately, I found out that it wasn't "calibrated" properly and was reading about 10 pounds low!

    You calibrate an instrument by using it to measure something that you already know. A thermometer in a factory might be calibrated by comparing it to another thermometer that has been previously calibrated.

    A person in the physics forum where you also posted this (and so my first sentence above) suggested that you put your sensor in ice-water which must have temperature 0 degrees C. I would recommend that you also put it in boiling water which must have temperature 100 degrees C. Those two values should allow you to determine the reading for other temperatures.
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