PHY 2048L
Lab 0

Error Analysis

Remember to hit the "reload/refresh" button to see changes made to this page.

Updated: 7/28/2004

Lecture on Uncertainties

There will be about an hour lecture on pages 1 thru 7 of the Lab Zero handout, covering significant figures, uncertainties (systematic and random), use of the standard deviation, and how to propagate uncertainties in mathematical calculations. You should pay particular attention to the difference between accuracy and precision. This info should enable you to do the prelab questions (due at the start of the next lab) and the problems in the Lab Zero report (which you should complete before the next lab). You should work on those problems during the lab so you can ask questions if anything is not clear.

Three equations from the handout on error analysis will be used regularly in the lab. The first is used to evaluate the mean (average) of a set of data

Equation for average (mean) of a data set   ,

while the second is used to calculate the sample standard deviation for that data set

Equation for the sample standard deviation   .

Every time you are asked to calculate an average value, you should also calculate the standard deviation. This is not hard to do on the TI-83 most of you own, and can also be done rather easily on most "2-line" scientific calculators such as the TI-30X IIS or Sharp EL-531. (The notation Sx is used in the equation because it is what the calculators use to refer to this quantity.) You would then calculate the standard error from the standard deviation

Equation for the standard error

if that is asked for in the lab writeup.


 ?? Contact me if you have any questions.