CONCEPT 4 Scientific Law. CONCEPT 3 Scientific Theory

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1 CONCEPT 1 Nature of Science is a way of learning about the natural world that is based on evidence and logic. The goal of science is to understand and things happen. Science advances as new evidence accumulates and allows scientists to,, or on accepted ideas about the natural world. CONCEPT 2 Scientific Induction is the process of drawing conclusions based on many pieces of evidence. This type of reasoning is the basis of the. In science, inductive reasoning is used to draw general conclusions from evidence. The conclusions are if necessary to explain new evidence as it becomes available. Inductive reasoning prove conclusively that an idea is true, but it may lead to conclusions that are very likely to be true. CONCEPT 3 Scientific Theory A is a broad explanation that is widely accepted because it is supported by a great deal of. Examples of theories in physical science include Dalton s atomic theory, Einstein s theory of gravity, and the kinetic theory of matter. The formation of scientific theories is generally guided by the law of. According to this law, the of competing theories is most likely to be correct. CONCEPT 4 Scientific Law A scientific is a statement describing what always happens under certain conditions. Newton s three laws of motion are examples of laws in physical science. A scientific law states what always but not it happens. Scientific theories answer why questions.

2 CONCEPT 5 History of Science Science has roots that go back thousands of years to Greek philosophers including Thales and Aristotle. The scientific method was introduced in the 700s by a Persian scientist named. Modern science began with the scientific revolution in Europe the 1500s and 1600s. The scientific revolution was launched by Copernicus new ideas about the. In the early 1900s, Einstein rocked science with his theory of gravity, which explained the concept in an entirely new way. CONCEPT 6 Scientific Process are at the heart of science. They produce evidence that helps scientists answer questions and better understand the world. Most scientists follow the same general approach to investigation, which is called the. It includes the following steps: ask a, do background research, construct a, test the hypothesis by doing an experiment, analyze the and draw a, and report the results. CONCEPT 7 Observation An is any information that is gathered with the senses. Observations raise that lead to scientific investigations. Observations also help scientists gather evidence in investigations. CONCEPT 8 Hypothesis In science, a is an educated guess that can be tested with observations and falsified if it really is false. You cannot prove conclusively that most hypotheses are true because it s generally impossible to examine all possible cases for exceptions that would disprove them. CONCEPT 9 Scientific Experiments An is a controlled scientific study of specific variables. A variable is a factor that can take on different values. There must be at least variables in any experiment: a variable and a variable. A is a variable that must be held constant so it won t influence the outcome of an experiment.

3 CONCEPT 10 Field Study In a study, a scientist gathers evidence in the instead of in a lab. Field studies are needed to investigate the. An example of a field study is collecting samples of river water to test for evidence of pollution. CONCEPT 11 Communication in Science The last step of most scientific investigations is the results of the research. When scientists share their findings, they add to the body of. They may also get useful from other scientists. Scientists may communicate about their research in several ways, such as presenting or at scientific conferences and publishing in scientific journals. CONCEPT 12 Replication in Science Getting the same result when an experiment is repeated is called. If research results can be replicated, it means they are more likely to be. Replication is important in science so scientists can. The result of an investigation is not likely to be well accepted unless the investigation is repeated many times and the same result is always obtained. CONCEPT 13 International System of Units The used by most scien2sts and engineers is the Interna2onal System of Units, or SI. There are seven basic SI units, including units for length and mass. If you know the English equivalents of SI units, you can convert SI units to English units or vice versa.

4 CONCEPT 14 Scientific Measuring Devices In science, length may be measured with a metric ruler using SI units such as and. Scientists measure mass with a, such as a triple beam balance or electronic balance. In science, the of a liquid might be measured with a graduated cylinder. CONCEPT 15 Accuracy and Precision means making measurements that are close to the. means making measurements that are close in value to each other but not necessarily close to the true value. CONCEPT 16 Calculating Derived Quantities are quantities that are calculated from two or more measurements. They include area, volume, and density. The area of a rectangular surface is calculated as its multiplied by its. The volume of a rectangular solid is calculated as the product of its,, and. The density of an object is calculated as its divided by its. A given derived quantity is always expressed in the same type of units. For example, area is always expressed in squared units, such as cm 2. CONCEPT 17 Significant Figures In any measurement, the number of is the number of digits thought to be correct by the person doing the measuring. It includes all digits that can be read directly from the measuring device plus one digit. To determine the number of significant figures in a measurement that someone else has made, follow the rules for counting significant figures. When measurements are used in a calculation, the answer cannot have more significant figures than the measurement with the significant figures. is done when one or more ending digits are dropped to get the correct number of significant figures. Simple rules state when to round up and when to round down.

5 CONCEPT 18 Scien/fic Nota/on is a way of writing very large or very small numbers that uses exponents. Numbers are written in the format: a 10 b. Changing numbers to or from scientific notation is easy to do by following three simple steps. CONCEPT 19 Descriptive Statistics are measures that summarize the characteristics of a sample. The, or center, of a sample can be represented by the mean, median, or mode. The in a sample can be represented by the range, or the total spread of values. CONCEPT 20 Scientific Graphing Graphs are very useful tools in science because they display data. Three commonly used types of graphs are,, and. Each type of graph is suitable for a different type of data. graphs are suitable for comparing values for different things, such as the average numbers of tornadoes for different cities. graphs are used to show percents of a whole, such as the percent of all U.S. tornadoes with different strengths. graphs are especially useful for showing changes over time, such as variation in the number of tornadoes by month throughout the year. CONCEPT 21 Scientific Modeling A is a representation of an object, system, or process that is simpler and easier to understand than the real thing. Examples of simple models in physical science include twodimensional models of molecules and electric circuits. CONCEPT 22 Safety in Science Lab safety symbols warn of specific, such as flames or broken glass. Knowing the symbols allows you to recognize and avoid the dangers. Following basic safety rules, such as wearing safety gear, helps prevent in the lab and in the field. All accidents should be reported.