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

Steps of theSteps of the Scientific MethodScientific Method

• Identify the problem, question, or a unique observation.

• Research the problem.

• Form a question and from there create a hypothesis & make a prediction.

• Test the hypothesis – experiment.

• Observe and record your results – analysis.

• Arrive at a conclusion or make a general rule – inductive or deductive.

ProblemProblem

The Problem is a scientific question to be solved. It is normally based on a problem that is:

1. Observed- using your senses and prior knowledge2. Researched- reviewing previous studies.

“ Why do recipes tell you to add salt to boiling water ?”

• Can be answered in a statement….. (usually an “if…then” statement is used) “If salt causes water to boil at a higher temperature, then it will cook the food faster .”

• 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.

ResearchResearch

Research is the process of collecting information from 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.

HypothesisHypothesis

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

“ I think salt changes how the water affects the food.”

• Experimenting will be designed to test the hypothesis.

• Do state facts from past experiences or observations on which you base 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.

ExperimentationExperimentation

“TESTING” the Hypothesis

• Know your “variables”

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

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

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

Ex. Amount of water used.

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)

•

ExperimentationExperimentation

• Does and Don’ts 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.

– Do have a control group.– Do have more than one control, with each

being identical.– Do organize data.

Observe and RecordObserve and Record

• Collect data

• Organize data- charts; graphs; tables; etc

• Analyze the data

• Pay attention to detail

• Interpretation and evaluation of results

• Write the results in a clear and concise

manner so others can understand them

ConclusionConclusion

After recording the results of the experimentation, you need a summary of the results and a statement of how the results relate

to the hypothesis. Remember:

* If your results do not support your hypothesis (refutes):

• DON'T leave out experimental results that do not support your hypothesis.• DON'T change your hypothesis.• DO give possible reasons for the difference between your hypothesis and the

experimental results.• DO give ways that you can experiment further to find a solution.

* If your results support your hypothesis: Reward yourself!

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.