PHY 2048L Lecture Notes - Lecture 1: Observational Error, Significant Figures, Approximation Error
Document Summary
To review the types of experimental errors and some methods of error and data analysis that will be used in subsequent experiments. Any measurement of physical quantities always involves some uncertainty or experimental error. Repeated measurements with random error give slightly different values each time. Avoiding systematic errors depends on the skill of the observer to recognize the sources of such error and to prevent or correct them: accuracy and precision. Good precision and good accuracy: significant figures. The significant figures of an experimentally measured value include all the numbers that can be read directly from the instrument scale plus one doubtful or estimated number (fraction of the smallest division). For example, the length of an object may be read as 2. 54 cm (three significant numbers) on one instrument scale and 2. 5405 cm (five significant numbers) on another. Thus, the significant numbers depend on the quality of the instrument and the fineness of its measuring scale.
