1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

How to write uncertainities on different measurement

  1. Jun 10, 2009 #1
    I need some advice on how to write uncertainities on different measurements.
    I need this urgently.
    Thanks:cool:
     
  2. jcsd
  3. Jun 10, 2009 #2
    Re: Uncertainties

    with a delta [tex]x \pm \Delta x[/tex]
     
  4. Jun 11, 2009 #3
    Re: Uncertainties

    i mean on measurements
     
  5. Jun 11, 2009 #4
    Re: Uncertainties

    [tex]x = (3.01 \pm 0.01) \text{ cm}[/tex]

    You mean like that? Otherwise, your question is so vague and general, I have no idea what you want.
     
  6. Jun 11, 2009 #5
    Re: Uncertainties


    That is it exactly what I want.
     
  7. Jun 11, 2009 #6
    Re: Uncertainties

    Well, what is your question about it?

    You simply write down the result of your measurement, and then you decide what the uncertainty is. You round the uncertainty to one significant digit (0.0193 becomes 0.02) and you round the measurement result to the same amount of digits (as long as they are in the same units). You then write it down as
    [tex]y = (x \pm \Delta x) \text{ [unit]}[/tex]
    where x is the measurement result and delta x the uncertainty.
     
  8. Jun 11, 2009 #7
    Re: Uncertainties

    Well my question was about the measurements in a ruler in mm and a protractor.
    I guess it would be +/-1 degree and +/- 0.5mm.
    Thanks for your help anyway.
     
  9. Jun 15, 2009 #8
    Re: Uncertainties

    Hi there,

    I believe I can help you with this one. The uncertainty of an analogue equipment is half the smallest measurement possible (0.5mm for your ruler). The uncertainty of a digital device is the smallest measurement possible (1mm for digital ruler that measures in mm).

    Cheers
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: How to write uncertainities on different measurement
  1. How to measure (Replies: 2)

Loading...