1. 1-2 How Science Works
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2. I. Scientific Hypothesis
Scientific Hypothesis A scientific hypothesis is a tentative explanation of an observation or pattern which has been observed in nature.
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3. Designing an Experiment
How do scientists test hypotheses? A hypothesis should be tested by an experiment in which only one variable is changed at a time.
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4. Designing an Experiment
The process of testing a hypothesis includes:
Asking a question
Forming a hypothesis
Setting up a controlled experiment
Recording and analyzing results
Drawing a conclusion
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5. How a Theory Develops
As evidence from numerous investigations builds up, a hypothesis may become so well supported that scientists consider it a theory. In science, the word theory applies to a well-tested explanation that unifies a broad range of observations.
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6. II. Scientific Theory
Scientific Theory A scientific theory is an explanation of a natural phenomenon with a broad range of significance and application.
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7. III. Scientific Law
Scientific Law A scientific law is an empirical (ie based on experimental evidence) statement of great generality of something which seems to always be true.
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8. IV. Differences between Hypothesis-Theory-Law
Scientific law is a generalization. It is NOT an explanation. It is the result of induction. It is an empirical (ie based on observation alone) statement of something which always appears to be true.
Hypotheses and theories, on the other hand, are an attempt to explain what has been observed. Often scientists form theories to explain laws.
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