# Physics

Pages: 2 (462 words) Published: April 17, 2013
Fawzi Abdelgani
Experiment 1: Experimental Uncertainty (Error) and Data Analysis Jan/30/2013

PRELAB:
1. Do experimental measurements give the rule value of a physical quantity? Explain. No. Statistical methods are used to establish the deviations in the measurement. 2. Distinguish between random (statistical) error and systematic error, and give an example of each. Random errors are caused by unknown and unpredictable changes in the experiment like mechanical vibrations of an experiment setup. Systematic errors are constant errors in the same experiment like an improperly zeroed scale. 4. What is the difference between measurement accuracy and precision? Explain the general dependence of these properties on the various types of errors. Accuracy is how close a measurement is to the actual measure. Precision is the agreement of repeated measures.

5. What determines how many figures are significant in reported measurement values? What would be the effect of reporting more or fewer figures or digits than are significant? All the numbers that can be measured plus one estimate number. It would give a slightly different result giving you a higher percent error. 6. In expressing experimental error or uncertainty, when does one use (a) experimental error and (b) percent difference? Experimental error is used when there is an excepted value. Percent difference is used when there isn’t an accepted value.

Objective:
* To learn how to properly take measurements of physical quantities. * Learn how to use experiential uncertainty or error.
* Recognize that there are random and systematic errors.
* Differentiate between precision and accuracy.
* How to use percent difference.

Conclusion:
Significant figures are the last digit of any measurement that is guessed/estimated. Significant figures are a way of getting a closer and better measurement of a physical object. Accuracy...