the scientific method scientific method an organized approach used to solve a problem or solution. a...
TRANSCRIPT
The Scientific Method
Scientific Method• An organized
approach used to solve a problem or solution.
• A list of steps that is not set in stone, rather it is used as a guide or frame for problem solving.
Hypothesis versus Theory
Hypothesis:• Explanation of an
Observation• Outcome • If I do….then I
expect……• correct or
incorrect
Theory:• Established idea
• Factual
• Experiments
• Data
Controlled Experiments
Control:• the part of the
experiment that is left alone or “natural”.
• Used to compare back to
Experimental • The part of the
experiment in which a factor or variable is changed.
Variables
• Variables are parts of an experiment that can be changed.
• Control (constant variables): factors in an experiment that are NOT changed.
Experimental Variables:
• Independent (manipulated) Variable: factors in an experiment that are changed.
• Good experiments have only ONE manipulated variable.
• Dependent (responding) Variable: responds to changes in the independent variable.
• Example: Measure growth in height as a result of no fertilizer
Observation vs. InferenceObservation• Description of objects,
eventsevents• May include data from
all five senses (touch/texture, smell, taste, sight, sound)
• Could be drawings, diagrams, written words
• Do not include opinionsopinions.
Inference
• Drawing conclusionsconclusions based on observations
• Often provide a reasonreason for the event/object being observed.
• Based on previous knowledge.
Data versus Opinion…...
Data:
• Factual
• Measurable
• Replicates
Opinion:
• Personal
• Inferences versus observations?
• bias
Scientific Data Must Be…..
• Measurable
• Quantifiable
• NOT opinion or judgment
7 Steps of the Scientific Method
• Problem or Question• Research• Hypothesis• Experiment• Collect and Analyze
Data• Conclusion• Communicate
Results
Identify the question• What question is
being answered, problem solved, or hypothesis tested?
• Leads to observations
• For example, “How many drops of water fit on a penny?”
Background research• Research the problem
using quality sources.
• Ask questions and read everything you can about the problem you have chosen.
• Study the method of measurement you will use to quantify your observations if it is one you are not familiar with.
State you hypothesis• Construct a Hypothesis: A
hypothesis is an explanation of an observation about how things work:
• "If _____[I do this] _____, then _____[this]_____ will happen."
• You must state your hypothesis in a way that you can easily measure, and of course, your hypothesis should be constructed in a way to help you answer your original question.
Design an experiment• The experiment tests whether
your hypothesis is true or false. • It is important for the experiment
to be a fair test. • Conduct a fair test by making sure
that you change only one factor at a time while keeping all other conditions the same.
• Repeat the experiments several times to make sure that the first results weren't just an accident.
Collect and Analyze data• Once the experiment is complete,
analyze the data to see if your hypothesis is true or false.
• Scientists often find that their hypothesis was false, and in such cases they will construct a new hypothesis starting the entire process of the scientific method over again.
• Even if they find that their hypothesis was true, they may want to test it again in a new way.
CONCLUSION• A conclusion summarizes how the results
support or contradict the original hypothesis.
• Summarize the results in a few sentences and use this summary to support or refute the hypothesis.
• Include key facts from your background research to help explain your results as needed.
• Summarize and evaluate your experimental procedure, making comments about its success and effectiveness.
• Suggest changes in the experimental procedure (or design) and/or possibilities for further study.
Communicate results• Communicate the results
to others in a final report.– publishing their final report
in a scientific journal– presenting their results on
a poster at a scientific meeting.