October 28th-- Class Blog Post By Greg Sra

Last class we learned about Accuracy & Precision, and the differences between them.

Precision:  How reproducible a measurement is compared to similar measurements.

Accuracy:  How close the measurement for average measurement comes to accepted or real value.

We Also Learned About Measurement & Uncertainty.
A measurement is just an estimate which has a certain degree of uncertainty. We also learned about Absolute Uncertainty. It is expressed in units of measure not in ratios.

 They're are two ways of calculating this. 

• The first is calculating the average of at least 3 measurements.The Absolute Uncertainty is the largest differential between the average and lowest/highest measurement.  

• The second method is determining the uncertainty of the measurements. When measuring you should get the most precise to do this you go to the smallest segment on the instrument. Take the smallest segment on the instrument and divide by 10. On a ruler the smallest measurement is 1mm then divide by 10 to get .1mm.

Relative Uncertainty is The   Absolute Uncertainty   
                                             Estimated Measurement

It can be shown as Percentage. Below is a link to Youtube
A Video About Measurement & Uncertainty