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Learn about the scientific method and its step-by-step process of defining problems, collecting information, forming hypotheses, testing them through experiments, making observations, and drawing conclusions. Discover the importance of accurate data recording and the distinction between observations and inferences. Understand how hypotheses can become scientific principles or theories. Be prepared for a quiz!
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THE PROCESS OF SCIENCE Using the Scientific Method
The Scientific MethodA logical, organized way of solving problems. • Define the Problem • Collect Background Information • Form a Hypothesis • Test the Hypothesis • Make and Record Observations • Draw a Conclusion
Identify the problem. Example: What are the effects of acid rain on salamanders? Collect information about the problem. Example: We should know the normal development of salamanders as well as the characteristics of areas that are affected by acid rain. Defining the Problem & Collecting Background Information
FORMULATE A HYPOTHESIS • An educated guess • A proposed answer to the question or problem. • A statement that can be tested
TESTING THE HYPOTHESIS p.1/2 • An experiment is a controlled procedure designed to test a hypothesis. • In an experiment, one variable, or condition, is changed and the response of another variable is measured.
Independent variable: the condition that is varied (or changed). Dependent variable: the condition that responds to the changes in the I.V. To be a controlled experiment, it must have two identical groups: Experimental group- the group that is exposed to the changes in the I.V. Control group- the group that is not exposed to changes. THE EXPERIMENT p.2/2
MAKING & RECORDING OBSERVATIONS p. 1/4 • Must keep careful records. • Must state how the experiment was planned, carried out, materials & equipment used, and how long it took. • Must record all observations made.
MAKING & RECORDING OBSERVATIONS p.2/4 • May include: drawings, tables, graphs, diagrams, written observations, photographs or even sound recordings.
Observation- an examination of something in nature. Detected by any of the five senses. Inference- a judgement based on your observation. It is a personal opinion. OBSERVATIONS VS. INFERENCES p.3/4
DRAWING CONCLUSIONS p.1/2 • The answer to a scientific question is formulated by drawing a conclusion based on data (scientific facts collected during the experiment) • Statistics help form the conclusion.
CONCLUSIONS p.2/2 • Before accepting conclusions, scientists retest their hypotheses several times. Later other scientists repeat the experiment until the hypothesis and the conclusion are supported or rejected.
LAW/THEORY p.1/2 • When a hypothesis explains how “facts of nature” occurs, it becomes scientific principle or law. Example: Law of Gravity • When a hypothesis explains why “natural” events occur through observations and investigations over a long period of time, it becomes a theory. Example: Theory of Evolution
THE PROCESS OF SCIENCE Be ready for a quiz