Quick Question on Uncertainty of PI

Thread starter circuscircus
Start date Sep 19, 2007
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Pi Uncertainty

AI Thread Summary

The discussion centers on understanding the uncertainty in the value of pi, specifically why it is expressed as 3.18 ± 0.04 instead of 0.012. The value 0.012 is identified as a relative error, calculated using the formula Δπ/π = 0.012. By rearranging this equation, the absolute error is derived as Δπ = 0.012π, which approximates to 0.04. This clarification highlights the distinction between relative and absolute errors in reporting uncertainty. Overall, the discussion emphasizes the importance of correctly interpreting and expressing uncertainty in mathematical constants.

Sep 19, 2007

circuscircus

Homework Statement

http://img413.imageshack.us/img413/226/8m1celf4.gif

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

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The Attempt at a Solution

Last edited by a moderator: May 3, 2017

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Sep 19, 2007

D H

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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

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