The Scientific MethodThe Scientific Method

ScienceScience is is a a methodicalmethodical approachapproach to learning about the to learning about the

world around usworld around us. .

Steps of theSteps of the scientific methodscientific method

• STATE THE PROBLEM

• CONDUCT RESEARCH

• HYPOTHESIS

• EXPERIMENT

• MAKE OBSERVATIONS & RECORD

• EXPRESS CONCLUSIONS

The Scientific method is a SCHEME for doing science

State the ProblemState the Problem

The Problem is a scientific question to be solved. It is normally found by:1. Observing- using your senses and prior knowledge2. Researcing- reviewing previous studies.

Example: “ Why are fish dying in the lake?”

Stipulations:

• Should be limited in it’s scope….. “We’re only researching the affects of salt.”

• Can be solved experimentally…… “Observe the affects as salt is added to water that is at boiling temperatures – under controlled conditions.

Collect InformationCollect Information

Collecting information is done by researching your own experiences, knowledgeable sources, and data from exploratory experiments to help you understand the topic .

• Do use many references from printed sources— books, journals, magazines, and newspapers—as well as electronic sources—

computer software and online services.

• Do gather information from professionals—instructors, librarians, and scientists, such as physicians and veterinarians.

HypothesizeHypothesize

A hypothesis is an idea about the solution to a problem, based on knowledge and research – an educated guess.

“ If salt is added then it will cause the food to cook faster.”

• Your experiment should be able to test the hypothesis.

• Do use the information you collected in determining your hypothesis.

• Do write down your hypothesis before beginning the project experimentation. (Generally write the hypothesis in an “if… then statement).

“If salt is added to boiling water then it will cause the food to cook faster”

• Don't change your hypothesis even if experimentation does not support it - that’s science! If time permits, repeat or redesign the experiment to confirm your results.

ExperimentExperiment

“TESTING” the Hypothesis

• Know your “variables”

Independent (manipulated) variable: is the variable you or the scientist purposely manipulate (change). Ex. Adding salt

Dependent (responding) variable: is the variable that changes in response to the independent variable Exp: water temp.

Controlled (constants) variables: are variables that are not changed.

Ex. Amount of water used, applying same amount of heat

Control Group: A group that is tested in which the independent variable is not applied. It is used as the standard by which the test results can be compared (Exp: Boiling the water without the salt added)

•

ExperimentExperiment

• Do’s of Experimentation:– Do have only one independent variable

during an experiment. All others must be controlled variables

– Do repeat the experiment to verify your results, if possible.

– Do have a control group..

Make observations of the Make observations of the experimentexperiment

• Collect data

• Organize data- charts; graphs; tables; etc

• Analyze the data

Evaluate and ConcludeEvaluate and Conclude

In this step you create a summary of the results and a statement of how the results relate to the

hypothesis.

ConclusionConclusion

• When writing a conclusion make sure to include the following:– Statements on how the results of the

experiment related to your hypothesis (whether it was supported or refuted)

– Explanations as to why the experimental results were achieved

– Other hypotheses that can be made based on the experimental results

– Any experimental flaws in your experiment

Theory vs. LawTheory vs. Law

• Theory- an explanation of things or events based on many observations and investigations

• Law- Statement about what happens in nature that seems to be true at all times.– Exp: Law of Gravity– Unlike theories…laws do NOT explain why.