## Chapter 1, Section 1 - The Nature of Science

Science Knowledge that you get by observing things in order to discover facts and create laws/principles that can be tested.

Technology The application of science for a practical purpose.

Law A statement/equation that reliably predicts events under certain conditions.
• Examples...
• Law of Gravity
• Newton's Laws of Motion
• Law of Conservation of Matter
Theory - A set of ideas that explains many related observations and is supported by a large body of evidence.
• Examples...
• Atomic Theory
• Big Bang Theory
• Evolutionary Theory
• Theories must...
• explain observations clearly and consistently.
• be able to be shown in experiments that can be repeated.
• allow you to predict the results of an experiment.
Models
• Physical Model
• Can be touched.
• Look/act like the real thing.
• Mathematical Model
• Made up of equations and data.
• Can include computer models, such as a weather map.
• Conceptual Model
• Made up of many hypotheses.
• Provide a reference - such as the atomic model.

## Chapter 1, Section 2 - The Way Science Works

Scientific Method
1. State the Problem (Ask a Question)
2. Background Research (What is already known?)
3. Make a Hypothesis (Educated guess to answer the question.)
4. Do an Experiment (To see if your hypothesis is right.)
• Make observations.
• Collect data (raw information - not organized).
5. Analyze the Data (Organize it, see what it means.)
6. Make a Conclusion (Accept/Reject/Modify your hypothesis.)
7. Communicate Your Results.
Variable - Something that changes in an experiment.
SI - International System of Units
• Seven base units - shown in the table at right.
• Derived units - made of combinations of base units.
• Volume
• Speed
• Pressure
• Force
• And so on...
• Prefixes used for large and small measurements...
• giga- (G) = billion
• mega- (M) = million
• kilo- (k) = thousand
• deci- (d) = one-tenth
• centi- (c) = one-hundredth
• milli- (m) = one-thousandth
• micro- (mc) = one millionth
• nano- (n) = one billionth

## Chapter 1, Section 3 - Organizing Data

Graphs
• Continuous Data
• Data that continues over time.
• Use a line graph.
• Discrete Data
• Data in clumps.
• Use a bar graph.
• Percent Data
• Data that reflects "part of the whole".
• Use a pie graph.
Scientific Notation - A method of expressing a quantity as a number multiplied by ten to a given power.
• 93,000,000 miles (from the Earth to the Sun) is written as 9.3 x 107
• 0.0000000199 is written as 1.99 x 108
• This is helpful for very large and very small numbers.
• When multiplying numbers written in Scientific Notation,...
• multiply the first numbers
• add the exponents on the powers of ten
• When dividing numbers written in Scientific Notation,...
• divide the first numbers
• subtract the exponents on the powers of ten
Significant Figures
• Tell you how to round off numbers, based on the precision of the measurement.
• Always use the number of significant digits of the least precise measurement.
• When adding/subtracting, you can't have more decimal places than the smallest number of decimal places.