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SCIENTIFIC METHODHow we solve problems
SCIENTIFIC METHOD The scientific method is a way to ask
and answer questions by making observations and doing experiments. Science is the process of doing this.
Observation: An act of noticing a fact or occurrence
What senses do we use to notice facts and occurrences?
OBSERVATIONS VS. INFERENCES
We use our five senses to observe things in nature.
We use our brain to make inferences based on these observations.
Inference: A conclusion reached based on evidence (observations) and reasoning
SCIENTIFIC METHODIt is important for your
experiment to be a fair test. A "fair test" occurs when you change only one factor (variable) and keep all other conditions the same.
Variable: a factor or item that is changed during an experiment
OVERVIEW OF THE SCIENTIFIC METHOD
Scientists use the scientific method to search for cause and effect relationships in nature. In other words, they design an experiment so that changes to one item (the independent variable) produces a measurable change in another item (dependent variable).
Constants: factors that are NOT changed during an experiment
Independent variable: the variable changed by the scientist during an experiment
Dependent variable: the variable being measured that changes as a result of changes to the independent variable
THE DEPENDENT VARIABLE DEPENDS ON THE INDEPENDENT VARIABLE!!!
Example: Various plant foods are applied to tomato plant seedlings. The growth of the tomato plants depends on the plant food used.
What are the variables in this experiment? Independent: _______________________________ Dependent: ________________________________
What other factors could affect plant growth? 1. 2. 3.In order for this to be a fair test of plant foods,
these other factors must be held constant.
BRAIN POP VIDEO CLIP
Scientific Method Video Clip
STEPS OF THE SCIENTIFIC METHOD
Ask a QuestionThe scientific method starts when you ask a
question about something that you observe. This may be identifying an effect (or problem) that has a yet to be identified cause.
In order for the scientific method to answer the question it must be about something that you can measure, preferably with a number.
Control: A standard to which your results may be compared
STEPS OF THE SCIENTIFIC METHOD
Do Background Research
Rather than starting from scratch, scientists use library and Internet research to help find the best way to do things and to avoid mistakes from the past.
STEPS OF THE SCIENTIFIC METHOD
Construct a Hypothesis: A hypothesis is an educated guess about how things work.
"If _____[I do this] _____, then _____[this]_____ will happen.”
Hypothesis: a prediction about cause and effect based on research.
STEPS OF THE SCIENTIFIC METHOD
Test Your Hypothesis by Doing an Experiment
Your experiment tests whether your hypothesis is true or false. It is important for your experiment to be a fair test. You conduct a fair test by making sure that you change only one factor at a time while keeping all other conditions constant (the same).
You should also repeat your experiments several times to make sure that the first results weren't just an accident.
STEPS OF THE SCIENTIFIC METHOD
Analyze Your Data and Draw a Conclusion
Once your experiment is complete, you collect your observations and analyze them 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.
STEPS OF THE SCIENTIFIC METHOD
Report Your ResultsTo complete your experiment you will
communicate your results to others in a final report and/or a display board. Professional scientists do almost exactly the same thing by publishing their final report in a scientific journal or by presenting their results on a poster at a scientific meeting.
Draw this in your
notebooks with colors!
SCIENTIFIC THEORIES AND LAWS
Scientific theory: An explanation or model backed by results from many experiments.
A hypothesis becomes a theory if it is supported by evidence over time.
Scientific law: A rule that describes the behavior of something in nature that just “is.”
An example is the law of gravity.
EARTH SCIENCEGeologyMeteorologyOceanographyAstronomy
GPS (GLOBAL POSITIONING SYSTEM):
A system that triangulates a person’s position on Earth by receiving signals from orbiting satellites. By comparing how far the person (receiver) is from each satellite, the person’s location is determined and displayed.
VIDEO!!!
VOCABULARY REVIEW Observations Inference Constant Independent Variable Dependent Variable Control Hypothesis Scientific Theory Scientific Law Global Positioning
System
Define and turn in using the paper cut
method!
