What is the scientific method? A systematic approach to problem-solving.

Hypothesis Observations Experiments Theory Scientific Law

Observations are facts you take in with your senses. They can be QualitativeQualitative QuantitativeQuantitative

Qualitative Observations Use words to describe – the color, odor, shape, texture, or some other physical characteristic.

Quantitative Observations Use numbers to describe a property. Result from measurement. Include a number and a unit. –Height, Mass, Temperature

What’s the difference between a fact and an inference? FactsFacts can be verified. They are objective. InferencesInferences are subjective. They involve conclusions drawn from data. –On Friday the 13 th I saw a black cat. –On Friday the 13 th I saw a spooky cat.

Hypothesis Testable, educated guess to explain or predict an observation.

Experiments An experiment is an organized process used to test a hypothesis. constant –Hold most variables constant. Independent variable –Manipulate one variable. (Independent variable. Controlled by the scientist.) Dependentvariable –Measure one variable. (Dependent variable.)

Control Control: Perform the experiment under specific conditions. A standard for comparison –Compare the experiment with the control. They should differ by only one variable.

Conclusion Judgment based on the experimental data. Does the experiment confirm the hypothesis or does the hypothesis need to be modified?

Theory or Model an overall explanation of some natural phenomenon. Ex: Kinetic Theory –Supported by many experiments –Can be modified as necessary –Can be used to make predictions

Scientific Law A relationship in nature that is supported by many experiments. –Law of Conservation of Energy –Newton’s Law of Gravitation

What’s the difference between a theory and a law again?

Theory vs. Law Attempt to explain why something happens. Summarizes what always happens.