Quick Question on Uncertainty of PI

1. Sep 19, 2007

circuscircus

1. The problem statement, all variables and given/known data
http://img413.imageshack.us/img413/226/8m1celf4.gif [Broken]

On b, why is the pi exp 3.18 +- 0.04 and not .012?

2. Relevant equations

3. The attempt at a solution

Last edited by a moderator: May 3, 2017
2. Sep 19, 2007

D H

Staff Emeritus
The 0.012 arises from $\Delta\pi/\pi = 0.012$. In other words, it is a relative error. Clearing the fraction gves the absolute error: $\Delta\pi = 0.012\pi\approx0.04$