process
DESCRIPTION
Science as a. process. Why is the sky blue?. Have you ever wondered why the sky is blue? One of the first science questions that was asked was why is the sky blue? They first made an observation : The sky is blue. They then asked the question: Why is the sky blue?. - PowerPoint PPT PresentationTRANSCRIPT
Science as a
Why is the sky blue?
Have you ever wondered why the sky is blue?One of the first science questions that was asked was why is the sky blue?
They first made an observation: The sky is blue.They then asked the question: Why is the sky blue?
What’s Next• Come up with a hypothesis with your neighbor for
the question: why is the sky blue?• Remember: A hypothesis means a testable
statement.• The hypothesis should be in the form of a
statement, (sentence) and the sentence needs to have the ability of being tested
So… Why is the sky blue?
• By: D. Gioffre, Hillsborough Middle School, Hillsborough, NJ 08844
• www.engineeringplanet.rutgers.edu• Pictures from:
– http://teacherweb.com/CT/MadisonMiddleSchool,Trumbull/MrCurry/links1.aspx
What is Scientific Method?
Process which outlines a series of steps used to answer questions.
What are the steps?1. OBSERVATION: Process of gathering information about events or processes.
2. HYPOTHESIS: An educated guess made to answer questions or problems.
3. EXPERIMENT: conducting a carefully controlled search for truth about a hypothesis.
4. CONCLUSION: Analyze results to see if the hypothesis is correct. If not, start over.
designing the
What is Experimental Design?
Includes two groups: Control and Experimental.
control group
Group where all factors are held constant. This is needed
for comparison!
experimental group
Group you are testing where only one factor is changed.
There are three variables within the experimental group:
Dependent, Independent, and Controlled.
dependent variable
The result. It’s what happened. What you measure.
The response.
The ‘’then” part of a hypothesis.
independent variable
The factor you purposely change/manipulate. It’s the
thing you are testing.
The ‘’if” part of a hypothesis.The ‘’if” part of a hypothesis.
controlled variables / constants
all factors which are NOT allowed to change during the
experiment
repeated trials
Experiments must be repeated several times using exactly the same conditions to see if the
results are consistent.
The more times you repeat the experiment, the more VALID your
results are.
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Theory vs. Hypothesis
Theory- A well tested explanation that brings
together many observations. It’s not a law and not absolute
truth!Supported by lots of
experimenting by lots of scientists.
Hypothesis- A proposed scientific explanation for a set
of observations.
Inference vs. Observation
Inference- making a decision based on what you already
know. Ex: We can’t test all the water, but we test a little and
know it’s safe. We infer that all the water is safe to drink.Observation- gathering
information about things in a careful, orderly way. We use our sight and hearing a lot when making observations.
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CONTR
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What group is this?What group is this?
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EXPER
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What are these called?What are these called?
CONSTANTS
00 22 44 66
What variable is this?What variable is this?The plant growth that you observe here can be called . . .
The plant growth that you observe here can be called . . . the results (of adding fertilizer) the results (of adding fertilizer) the response (to adding fertilizer) the response (to adding fertilizer) the effects (of adding fertilizer) the effects (of adding fertilizer)
dependent
variable
amt. of wateramt. of water
type of planttype of plant
type of plantertype of plantersize of plantersize of planter
amt. of soilamt. of soil
type of lighttype of light
locationlocation
type of soiltype of soil
What do you do if you want to test the type of soil instead of
fertilizer?
fertilizerfertilizer
Type of soil becomes the IV.Fertilizer becomes a constant.
iviv dvdvconstantsconstants
plant growthplant growth
fertilizerfertilizertype of soiltype of soil
Evaluate the experimental design in
the next two slides.
Dirt: The New Muscle Juice
• Eight year old• Play with trucks• 2 months• Give water
• Eighteen year old• Weight lifting• 6 months• Give Dirt
Which kid will be stronger?
Good experiment?
Questions• What are the controlled variables?• What is the independent variable?• What would be the dependent variable?
forming a
iviv dvdv
plant growthplant growthfertilizerfertilizer
constantsconstants
amt. of wateramt. of water
type of soiltype of soil
type of planttype of plant
type of plantertype of planter
size of plantersize of planter
amt. of soilamt. of soil
type of lighttype of light
locationlocation
If fertilizer
+ verb +
ver
b
then plant growth
is added to plants, will improve.
Take 7 minutes to design an experiment using the IVCDV chart to test the strengths of various sunscreen on aliens.
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