1. Lesson 1-3a Accuracy, Precision and Certainty Pg 17 and 18

2. Accuracy and Precision Accurate –How close are a set of results to a true value? –Accurate results may be imprecise! Precise –How close are individual measurements to one another? –Precise results may be inaccurate! Accurate and Precise –The goal for all scientists!

3. Uncertainty in Measurement All measurements have some uncertainty When recording data, scientists record all numbers they know for sure, then write down their best guess for the number of which they are not sure The last digit in a number is always the uncertain digit 0.12 or 0.13? We estimate as 0.125 some might argue 0.124 or 0.126 Since there is no mark on the cylinder the last digit is uncertain 0.10 0.15

4. Lab Lab 1-3: Equipment and Measuring