Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Scientific Measurement Chapter 3 Qualitative and Quantitative Measurement: Qualitative measurement: Results are descriptive Results are in non- numerical form (Quality) Many, fuzzy, blue Qualitative and Quantitative Measurement: Quantitative measurement: Results are in definite form Results are given in number and units (Quantity) 6 mL, 38 mph, 5 feet tall Accuracy, Precision, Error What do we mean by accuracy? A measurement of how close a measurement comes to the actual or true value of what ever is measured. Accuracy, Precision, Error How about precision? A measure of how close a series of measurements are to one another. Accuracy, Precision, Error What is error? The difference between accepted and experimental values. % error To calculate % error, use the following equation: Accepted – experimental value x 100% accepted value Units of Measurement: SI (International System of Units) Quantity Length Time Mass Temperature Amount of substance Energy Unit Meter (m) Second (s) Kilogram (kg) Kelvin (K) Mole (mol) Joule (J) Scientific Notation In science, we deal with very small and very large numbers: 1 mole= 602000000000000000000000 Mass of electron= 0.0000000000000000000000000000000 91 kg Scientific Notation A method of representing very large of small numbers in the form: M x 10n Where: M is a number between 1 and 9.9 n is an integer . 2 500 000 000 9 8 7 6 5 4 3 2 1 Step #1: Insert an understood decimal point Step #2: Decide where the decimal must end up so that one number is to its left Step #3: Count how many places you bounce the decimal point Step #4: Re-write in the form M x 10n 2.5 x 9 10 The exponent is the number of places we moved the decimal. 0.0000579 1 2 3 4 5 Step #2: Decide where the decimal must end up so that one number is to its left Step #3: Count how many places you bounce the decimal point Step #4: Re-write in the form M x 10n 5.79 x -5 10 The exponent is negative because the number we started with was less than 1. Practice 159302 900024 0.000426 0.002