Scientific Method Scientific Method and Moreand More

Defining ScienceDefining Science

ScienceScience – “to know” – “to know”

Pure SciencePure Science research that adds to the body of scientific research that adds to the body of scientific

knowledge knowledge has no practical usehas no practical use

Applied ScienceApplied Science (Technology) (Technology) the practical application of scientific knowledgethe practical application of scientific knowledge

Defining ScienceDefining Science

PUREPURE

human geneticshuman genetics

polymer science polymer science

atomic theoryatomic theory

study of the study of the human earhuman ear

APPLIEDAPPLIED

DNA fingerprintingDNA fingerprinting

LycraLycra®® spandex spandex

nuclear weaponsnuclear weapons

hearing aidshearing aids

3 main areas of science3 main areas of science

1. Biology1. Biology The study of living thingsThe study of living things2. Physical science2. Physical science The study of physics and chemistryThe study of physics and chemistry3. Earth science3. Earth science The study of Earth and the universeThe study of Earth and the universe

Some Science TermsSome Science TermsHypothesisHypothesis – an educated guess, a prediction – an educated guess, a prediction about what you think WILL happenabout what you think WILL happen

TheoryTheory– explanation of things or events that is – explanation of things or events that is based on evidence gained from many based on evidence gained from many observationsobservations Examples:Examples:

Scientific Law Scientific Law – statement about how things – statement about how things work in nature that seems to be true all the time.work in nature that seems to be true all the time. Examples:Examples:

Scientific MethodScientific Method

Organized set of investigation procedures.Organized set of investigation procedures.To find the answer to a problem.To find the answer to a problem.

Scientific MethodScientific Method

1. State the Problem1. State the Problem2. Gather Information on the problem3. Form a Hypothesis4. Perform the Experiment5. Record and Analyze Data6. State a Conclusion***** Repeat the Work *****

VariablesVariablesVariableVariable– literally means “something changes”– literally means “something changes”Independent Independent VariableVariable – the variable the – the variable the experimenter controls and changes in an experiment experimenter controls and changes in an experiment …. Graphed on the X-axis…. Graphed on the X-axisProblem: How does Problem: How does lightlight effect the growth of tulips? effect the growth of tulips?

IV: the IV: the amountamount of light of light given to the tulipsgiven to the tulips

Experiment setupExperiment setup

Group 2 Group 3

Group 4

Group 1

Dependent Dependent VariableVariable– the thing you – the thing you _________________ _________________ in an experiment in an experiment (this changes because of the independent (this changes because of the independent variable)… plotted on the y-axis of a graphvariable)… plotted on the y-axis of a graphProblem: How does light effect the Problem: How does light effect the growth growth of tulips?of tulips?

DV: the growth DV: the growth of the tulip of the tulip

(height)(height)

ControlControl– set up exactly like the experiment, but – set up exactly like the experiment, but has no independent variable in it (also called has no independent variable in it (also called “control group”)“control group”)

Constants Constants – these are factors that are kept THE – these are factors that are kept THE SAME among all experimental groups.SAME among all experimental groups.Same amount of water, same type of plant, Same amount of water, same type of plant, same amount of plant food, same type of soil, same amount of plant food, same type of soil, same size container, etc.same size container, etc.

Try this…Try this…

Problem: Which laundry detergent cleans Problem: Which laundry detergent cleans grass stains out of jeans better?grass stains out of jeans better?Hypothesis: _____________ will clean Hypothesis: _____________ will clean grass stains out of jeans better than grass stains out of jeans better than ____________________.____________________.IV:IV:DV:DV:Constants:Constants:

Any Questions?Any Questions?

Get with a partner!Get with a partner!Problem: Which type of mouthwash kills bacteria Problem: Which type of mouthwash kills bacteria better?better?Hypothesis: (make sure it encompasses both the Hypothesis: (make sure it encompasses both the IV and the DV)IV and the DV)IV:IV:DV:DV:Constants:Constants:How would a control group be set up?How would a control group be set up?

GraphsGraphs1.1. Line GraphLine Graph

Used for showing changes that occur in related Used for showing changes that occur in related variablesvariables

Independent variable plotted on x-axisIndependent variable plotted on x-axis Dependent variable plotted on y-axis Dependent variable plotted on y-axis

Can be directly proportionalCan be directly proportional

Or inversely proportionalOr inversely proportional

GraphingGraphing

2. Bar Graphs2. Bar GraphsUsed to compare a set of measurements, Used to compare a set of measurements, amounts of changesamounts of changes

3. 3. Circle Graph or Pie ChartsCircle Graph or Pie ChartsA circle divided to show A circle divided to show

how a part of something how a part of something relates to the wholerelates to the whole