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This chapter explores the methods of science, including investigations, measurements, variables, and the use of technology. It also discusses the importance of accuracy and precision in scientific measurements and introduces the International System of Units (SI) for measuring length, volume, and more.
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Chapter 1 The Nature of Science
I. The Methods of Science A. Review Vocabulary: Investigation to observe or study by close examination.
I. The Methods of Science • Science means “having knowledge.”
I. The Methods of Science C. Science → is a process that uses observation and investigation to gain knowledge about events in nature.
I. The Methods of Science D. There are three major categories of Science: 1. Life science deals with living things. 2. Earth science investigates Earth and space. 3. Physical science deals with matter and energy.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem. 2. Gather information.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem. 2. Gather information. 3. Make a hypothesis.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem. 2. Gather information. 3. Make a hypothesis. 4. Test the hypothesis.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem. 2. Gather information. 3. Make a hypothesis. 4. Test the hypothesis. 5. Analyze the results.
E. Scientific Methods → an organized set of investigation procedures. 1. Identify a problem. 2. Gather information. 3. Make a hypothesis. 4. Test the hypothesis. 5. Analyze the results. 6. Draw conclusions.
F. Hypothesis → a possible solution or an explanation that is consistent with what is known.
G. Experiment → an organized procedure for testing a hypothesis; tests the effect of one thing on another under controlled conditions.
H. Variables → factors that can cause a change in the results of an experiment.
I. Dependent Variable → factor that changes as a result of changes in other variables.
J. Independent Variable → a factor that, as it changes, affects the measure of another variable.
K. Constant → variable that (does, does not) change when other variables change.
Control → standard used for comparison of test results in an experiment.
Bias → occurs when a scientist’s expectations change how the results of an experiment are viewed.
N. How can bias be lessened? 1. By running as many trials as possible. 2. By keeping accurate notes.
O. Valid experiments also must have data that are measurable.
Q. Model → can be used to represent an idea, object or event that is too big, too small, too complex, or too dangerous to observe or test directly.
R. Scientific Theory → an explanation of things or events that is based on knowledge gained from many observations and investigations.
S. If scientists repeat an investigation and the results always support the hypothesis, the hypothesis can be called a theory.
U. Scientific Law → a statement about what happens in nature that seems to be true all the time; does not explain why or how something happens.
Technology → is the application of science to help people.
II. Standards of Measurement A. Review Vocabulary: Measurement the dimensions, capacity, or amount of something.
II. Standards of Measurement B. A standard is an exact quantity that people agree to use to compare measurements.
II. Standards of Measurement C. Precision → describes how closely measurements are to each other and how carefully the measurements were made.
D. Accuracy → compares a measurement to the real or accepted value.
E. When taking measurements, it is important to be precise andaccurate.
F. International System of Units 1. The system used today by all scientists is called the International System of Units or (SI). 2. Each type of SI measurement has a base unit.
Mars Orbiter Lost – $125 Million Oops! Miscommunication of English vs. Metric Units.
3. Prefixes are used with the names of the units to indicate what multiple of ten should be used with the units.
Practice: 1. 1 meter = ____ centimeters 2. 1 kilometer = _____meters 3. 1 liter = ______ milliliters 4. 1 gram = ______ kilograms 5. 1 decimeter = ______ meters 6. 12 decimeters = ______ meters 7. 54 kilograms = ______ grams 8. 2 liters = ______ hectoliters
G. Measuring Distance 1. Length is the distance between two points. 2. The SI base unit of length is the meter (m). • Why is choosing the correct unit of length important? To avoid large digit numbers and numbers with many decimal places.
H. Measuring Volume 1. Volumethe amount of space occupied by an object. 2. If you want to know the volume of a solid rectangle you would multiply the length, width and height together. 3. If the sides were measured in centimeters, the volume would be expressed in cubic centimeters (cm3).
4. In measuring a liquid’s volume, you are indicating the capacity of the container that is holding the liquid. 5. The most common units for expressing liquid volume are liters(L) and milliliters (mL).
6. One liter occupies the same volume as a cubic decimeter (dm3). {1 L = 1 dm3} 7. Also, important to know is 1 mL = 1 cm3.
I. Measuring Matter 1. Mass the amount of matter in an object. 2. Mass is constant. This means that mass DOES NOT change anywhere you go. 3. (True, False) You have the same mass on Earth as you would on the moon. 4. The standard unit of mass is the kilogram.
5. Weight is a measure of the gravitational force on an object. 6. Your weight would be different on the moon because the moon has (more, less) gravity. 7. The standard unit of weight is the Newton.
Mass and weight are NOT the same thing!
8. Density is the mass per unit volume of a material. 9. Density can be found by dividing an object’s mass by its volume. 10. The equation looks like this: D = m/v 11. The standard unit for density is g/cm3.
J. Measuring Time and Temperature 1. Time is the interval between two events. 2. The SI unit for time is the second (s).
3. Temperature is the measure of how hot or cold something is. 4. For most scientific work, temperature is measured on the degree Celsius (°C) temperature scale.
