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Homework Help: Sensitivity expression

  1. Mar 31, 2007 #1
    I have a question about the sensitivity of measurements in experiments.
    e.g. We measure the current of a circuit and it's 1A. if the sensitivity is 1 part in 100, does that mean we can't distinguish the current between 1-1/100A and 1+1/100A?

  2. jcsd
  3. Mar 31, 2007 #2
    Thanks, that's what i meant
  4. Mar 31, 2007 #3
    Whoops I just told you the wrong thing. I just told you about resolution.

    Sensitivity is the change in output/ the change in input.

    So if you have a change of 1V in your circuit, the instrument will show a change in 1/100 V.
  5. Mar 31, 2007 #4
    ya, so it can't tell when the change is smaller than 1/100V, right?
  6. Mar 31, 2007 #5
    No, thats not what sensitivity is. Its the ratio of the change in input to the change in output. Thats totally different from what I told you at first, the resolution.
  7. Mar 31, 2007 #6
    Sorry, but i'm confused now.
    Let's just stick to the example i mentioned. the initial current is 1A and the sensitivity of the ammeter is 1 part in 100. And if the current changed from 1A to (1+1/1000)A, what value will be displayed on the ammeter?
  8. Apr 1, 2007 #7
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