Chapter 1 - H “Science Skills”

1.1 What is Science? 1.List as many pieces of technology as you can that are on or a part of your desk. 2.The application knowledge to solve practical problems is known as _________________________. 3.List the 3 main branches of science. 4.Which branch will we cover in this class? 5.What is required EVERY DAY in this class? 6.What is Mrs. Ferrer’s Homework Policy about due dates? 7.What is her policy about coming into class after the bell?

1.1 What is Science?

1.1 “What is Science?” a method of acquiring knowledge A process A body of knowledge STEPS: Curiosity Methods Discovery

1.1 What is Science? Technology Technology The use of knowledge to solve practical problems. The use of knowledge to solve practical problems.

1.2 A Scientific Method

VARIABLES: 1.Manipulated (independent) – what YOU change on purpose 2.Responding (dependent) – what YOU measure as a result of what you changed 3.CONTROL – the experiment WITHOUT the I.V. (manipulated variable) 4.Controlled Variables (constants) – all other components MUST stay the same for each trial 5.Uncontrolled Variables – the components you CANNOT control

1.2 A Scientific Method

Scientific Facts – observed results Scientific Theory (e.g. Kinetic Theory, Germ Theory, Evolution) – well-tested explanation of results/observations (never proven) Scientific Laws (e.g. gravity, Ohm’s law, conservation) – a pattern found in nature Scientific Models (e.g. atoms, weather) - r r r representation of a object or event

FOLLOW-UP 1. Scientific investigations begin with ____________. 2. The application of knowledge to solve practical problems is known as ________________. 3. What is the purpose of an experiment? 4. Write a couple sentences describing how advances in technology have affected your life. 5. Design Your Own Experiment Suppose that you want to conduct a test to see which brand of cleanser produces the best results when cleaning a kitchen floor. Think about how you would conduct this test. 1.What materials would you need? 2.What procedure would you follow? 3.How would you determine which cleanser produces the best results? LAB SAFETY LAB SAFETY

1.3 Journal “ Measuring Length by the Handful” The English units that we use in the United States developed over a long period of time. For example, the hand was devised in ancient times as a unit of length. It was defined as the length of a person’s hand from the little finger to the thumb. Today the height of horses is still measured in hands, but the definition of a hand is standardized at 4 inches or centimeters. 1.Why did the hand produce unreliable measurements before it was standardized? 2.Measure the height of your desk in hands. Compare your results with other classmates. How do the results vary? 3. WORK ON METRICS MANIA

1.3 Measurement Measurements in science are DATA. It is important that they are both accurate and precise.

Precision vs. Accuracy Precision = exactness (more significant digits: 1.256m stride, not 1m) Accuracy = closeness to actual value. (using a quartz or atomic watch instead of counting in your head) try it.

SCIENTIFIC NOTATION A way of expressing a value by powers of 10. Make very large and very small numbers easier to work with.

For practice, write these numbers out in long form.

Turn to page 15, Math Practice

1.3 Measurement International System of Units (SI) MEASUREMENTS ALWAYS HAVE A NUMBER AND A UNIT 4m, 25s, examples?????? Allow scientists from all over the world to understand one another’s measurements

Derived Units QuantityUnitSymbol Areasquare meterm² Volumecubic meterm³ Densitykilograms per cubic meterkg/m³ Pressurepascal (kg/ms²)Pa Energyjoule (kgm²/s²)J Frequencyhertz (1/s)Hz Electric chargecoulomb (As)C

1.3 Measurement - PREFIXES PrefixSymbolFactor NumberFactor Word gigaG1,000,000,000 (10 9 )billion megaM1,000,000 (10 6 )million kilok1,000 (10 ³ )thousand hectoh100 (10 ² )hundred decada10ten Base unitm, g, L1meter, gram, Liter decid1/10 (10 ˉ¹) tenth centic1/100 (10 ˉ² )hundredth millim1/1,000 (10 ˉ³ )thousandth microm1/1,000,000 (10 -6 )millionth Try some conversions

1.4 Presenting Scientific Data - Journal 1. “ Evaluating Precision” Lab: 1. R ead and do page 1 2. R ead page 2

1.4 Presenting Scientific Data Data: the measurements and observations taken during an experiment. Need to be ACCURATE (reliable) and PRECISE (exact) in order to be able to answer the hypothesis.

Must also be presented in a way that can be understood and analyzed. DATA TABLES: show the relationship between your independent (manipulated) and dependent (responding) variables. CategoryMass of Waste paper 15kg plastic3kg glass9kg metals8kg yard wastes4kg food wastes7kg other2kg TOTAL38kg

1.4 Presenting Scientific Data Must also be presented in a way that can be understood and analyzed. GRAPHS: show the relationship between your independent (manipulated) and dependent (responding) variables IN A WAY THAT IS EASIER TO ANALYZE

Bar Graphs: Compare sets of measurements, amounts or changes.

Circle Graphs: Show how a PART relates to the WHOLE.

Line Graphs: Show CHANGES that occur in related variables, and HOW they’re related.

Mass vs. Volume of Water – DIRECTLY PROPORTIONAL Figure 21: Mass vs. Volume of Water – DIRECTLY PROPORTIONAL The slope tells the relationship between the variables.

Distance vs. Light Intensity – INVERSELY PROPORTIONAL Figure 21: Distance vs. Light Intensity – INVERSELY PROPORTIONAL