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!

Dividing a number w/uncert by a number w/o uncert

  1. Sep 25, 2011 #1
    1. The problem statement, all variables and given/known data
    If I have a number with an uncertainty and I want to divide it by a number without an uncertainty (ex. if it's just a constant, like pi), what do I do with the uncertainty? Is it ok to just divide the uncertainty by that number?

    ex. (4.05 +/- 0.3) / 3

    Do I divide the 0.3 uncertainty by 3, and that would be my uncertainty for the final answer, or do I have to do percentage uncertainties?


    2. Relevant equations
    N/A


    3. The attempt at a solution
    Intuition tells me it's the first, but I'm not sure.
     
  2. jcsd
  3. Sep 25, 2011 #2
    (4.05 +/- 0.3) / 3 = (4.08 to 4.02) / 3 = 1.36 to 1.34 = 1.35 +/- 0.1

    So I think you are right.
     
  4. Sep 26, 2011 #3
    Yes, the uncertainty is also mulitplied (or divided, in this case) by the constant.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Dividing a number w/uncert by a number w/o uncert
  1. Finding force w/o mass (Replies: 2)

  2. Magnetism w/o calculua (Replies: 1)

Loading...