Chronology |
Current Month |
Current Thread |
Current Date |

[Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |

*From*: John Denker <jsd@av8n.com>*Date*: Tue, 05 Sep 2006 14:00:13 -0400

fizix29@aol.com wrote:

Let a = 40 +/- 5 m

b = 30 +/- 3 m

t = 1.2 +/- 0.1 s

What is a + b and a/t?

Assuming the inputs are Gaussian and IID, then:

a+b is 70±5.8 Gaussian distributed

a/t is 33.3±4.8 nearly, but not quite Gaussian distributed

The a+b result is easily obtained algebraically; the uncertainties add in

quadrature.

http://www.av8n.com/physics/uncertainty.htm#sec-manual-prop

A fair approximation to the a/t result could also be obtained algebraically

(hint: take logarithms) but I found it easier to just do the Monte Carlo.

http://www.av8n.com/physics/uncertainty.htm#sec-mg-mass

**Follow-Ups**:**Re: [Phys-l] propagation of error***From:*Jack Uretsky <jlu@hep.anl.gov>

**References**:**[Phys-l] propagation of error***From:*fizix29@aol.com

- Prev by Date:
**[Phys-l] propagation of error** - Next by Date:
**Re: [Phys-l] propagation of error** - Previous by thread:
**[Phys-l] propagation of error** - Next by thread:
**Re: [Phys-l] propagation of error** - Index(es):