Transcript CHAPTER ONE
PHYSICAL SCIENCE CHAPTER ONE INTRODUCTION TO SCIENCE 1.1 THE NATURE OF SCIENCE Is science: a set of FACTS? OR an ongoing PROCESS? BRANCHES OF SCIENCE LIFE SCIENCE PHYSICAL SCIENCE EARTH SCIENCE ? ? How do pure science and technology depend on each other? A ________ THEORY is a tested (when possible) explanation (how or why) of a natural event. The KINETIC MOLECULAR THEORY states that molecules are in constant motion. Use this theory to explain why the balloon takes the shape it does. Use the KINETIC theory to explain why the handle of a camp fork gets hot. LAW states a summary of a A _____ repeated observation about a natural event in God’s creation. A MODEL is a _______ of an object or event. MODELS MAY BE: drawings mental pictures a set of rules physical objects computer pictures Identify some models in our classroom…. Identify some things in the classroom that are NOT models… THE WAY SCIENCE WORKS 1.2 It is a way of THINKING THE SCIENTIFIC METHOD is a way to organize your thinking. After making observations… 1. Question 2. Collect Data 3. Hypothesis 4. Experiment – only one variable!!! All other conditions controlled!!! Using the Scientific Method to improve 5. Conclusion your social life. It is using scientific TOOLS. Name some tools found in our classroom… It is using the METRIC system of measurement. UNIT TOOL LENGTH MASS VOLUME TEMPERATURE CLICK FOR A MEASUREMENT PRESENTATION http://pc65.frontier.osrhe.edu/hs/science/ppt/ps02.ppt SI - International System of Units 1. Based on multiples of 10 2. Common metric prefixes: a. b. c. d. e. f. g. h. mega- (M) kilo- (k) hecto- (h) deka- (da) deci- (d) centi- (c) milli- (m) micro- (u) 1 000 000 x 1 000 x 100 x 10 x 0.1 x (1/10) 0.01 x (1/100) 0.001 x (1/1000) 0.000 000 001 x Jason goes metric… 1.3 ORGANIZING DATA LINE GRAPHS • MOST OFTEN USED IN SCIENCE • DISPLAY DATA THAT IS CHANGING • TWO VARIABLES – _________________ “I choose this variable!” – _________________ “this depends on what happens” How to Construct a Line Graph Making Science Graphs and Interpreting Data BAR GRAPHS • TO COMPARE DATA FOR INDIVIDUAL ITEMS PIE CHARTS • TO DISPLAY DATA THAT ARE PARTS OF A WHOLE Accuracy or Precision? • Accuracy vs. Precision – Accuracy – a statement of how close a measured value is to the true or accepted value. – Precision – a statement of how reproducible the measured results are. COMPARE AND CONTRAST ACCURACY 1. 2. 3. 4. PRECISION 1. 2. 3. 4. WHICH WOULD YOU PREFER? Scientific Notation • What- a value written as a simple number multiplied by a power of 10. – The sun is 93 X 106 miles from earth. • Why? – Very large or very small numbers are written this way as a form of number “shorthand”. Scientific Notation What Is the Standard Form of These Tens? 2 10 3 10 4 10 5 10 100 1,000 10,000 100,000 Exponents of Ten Notice that the number of zeros matches the exponent number… 2 10 3 10 4 10 5 10 100 1,000 10,000 100,000 What is the Exponent Form? 500 = 5 x 10 2 Scientific Notation and Accuracy or is it Precision??? Why did mom use scientific notation? Is the word “accuracy” used properly here? Significant Figures • Significant Figures – The value reported for a measurement is rounded off so that it contains only the digits known with certainty plus one uncertain one which is the last digit. • Significant Figure Rules – To determine the number of significant figures in a reported value, start at the left and count all digits beginning with the first non-zero digit. Examples: 0.003040 => 4 sig. fig. 10,200 => 5 sig. fig. Significant Figures • Significant Figures in Calculations – Addition & Subtraction: The number of decimal places in the answer should be equal to the number of decimal places in the value with the fewest decimal places. Example: 12.0035 g 3.72 g 0.015 g 15.74 g (4 decimal places) (2 decimal places) (3 decimal places) (2 decimal places) Significant Figures • Significant Figures in Calculations – Multiplication & Division: The number of significant figures in the answer should be the same as the value with the fewest significant Example: figures. 12.36 mL 4 sig. fig. x 2 sig. fig. 1.7 g mL = 21 g 2 sig. fig. – Note: Definitions and counted numbers have an unlimited number of significant figures. And now to prepare for the test… • Know the branches of science. • Understand how pure and applied science differ. • Know how laws, theories, and models are alike and how they are different. • Understand metric measurement: mass length, and volume. • Types of graphs and variables. • Accuracy, precision, significant figures, scientific notation.