THE SCIENTIFIC METHODTHE SCIENTIFIC METHOD

““Knowledge comes from asking Knowledge comes from asking the right questions.”the right questions.”

The Scientific MethodThe Scientific Method

A A processprocess used by scientists to find used by scientists to find answers to questions or to solve a answers to questions or to solve a problem.problem.

STATE THE PROBLEMSTATE THE PROBLEM

Write a Write a QuestionQuestion that that asksasks what what

you want to you want to know.know.

EXAMPLEEXAMPLE

When a golf ball, a When a golf ball, a tennis ball, and a tennis ball, and a wiffle ball are wiffle ball are dropped from the dropped from the same height, which same height, which ball will bounce ball will bounce highest?highest?

COLLECT INFORMATIONCOLLECT INFORMATION

Information Information may come from may come from

previous previous experience experience

(observations) (observations) or from or from

research.research.

EXAMPLESEXAMPLES Experience: Experience: Golf balls Golf balls

are heavier than wiffle are heavier than wiffle balls.balls.

Experience:Experience: Wiffle balls Wiffle balls are smoother than are smoother than tennis balls.tennis balls.

Research:Research: Which of the Which of the balls are designed to balls are designed to bounce?bounce?

Research:Research: Which ball Which ball contains the most contains the most rubber?rubber?

FORM A HYPOTHESISFORM A HYPOTHESIS

Make an Make an educatededucated guess about what guess about what the answer to the the answer to the problem will be. problem will be. The The hypothesishypothesis

should be based on should be based on the the informationinformation

collected.collected.

EXAMPLEEXAMPLE

Based on research Based on research the golf ball will the golf ball will likely bounce the likely bounce the highest because it is highest because it is the heaviest of the the heaviest of the three balls and it is three balls and it is designed to bounce.designed to bounce.

TEST THE HYPOTHESISTEST THE HYPOTHESIS

DesignDesign and and PerformPerform an an

experiment to experiment to test your test your

hypothesishypothesis..

EXAMPLEEXAMPLEMaterialsMaterials

1 – tennis ball1 – tennis ball 1 – golf ball1 – golf ball 1 – wiffle ball1 – wiffle ball 1 – meter stick1 – meter stick

Procedure-(Steps)Procedure-(Steps)1.1. Drop each ball from a height of Drop each ball from a height of

1 meter.1 meter.2.2. Measure the height of each Measure the height of each

ball’s first bounce. (Measure ball’s first bounce. (Measure from the bottom of the ball.)from the bottom of the ball.)

3.3. Repeat steps 1 and 2 four times Repeat steps 1 and 2 four times for each ball.for each ball.

4.4. Average the four trials for each Average the four trials for each ball.ball.

ORGANIZE AND ANALYZE DATAORGANIZE AND ANALYZE DATA

The The resultsresults of an of an experiment can be experiment can be recorded in many recorded in many different ways. different ways.

TablesTables or charts are or charts are useful for recording useful for recording data in an organized data in an organized way. way. GraphsGraphs can be can be

used to compare used to compare results.results.

EXAMPLEEXAMPLE

Type of ballType of ball Avg. Height of Avg. Height of bounce bounce

(cm)(cm)

WiffleWiffle 2020

tennistennis 5555

golf golf 7171

WRITE A CONCLUSIONWRITE A CONCLUSION

Write a Write a statementstatement that that compares the compares the

hypothesishypothesis to the data to the data and answers the and answers the

question stated in the question stated in the problemproblem. It will either . It will either prove or disprove the prove or disprove the hypothesis. Results hypothesis. Results

that do not that do not supportsupport the the hypothesis may lead to hypothesis may lead to

a a newnew or or revisedrevised experiment.experiment.

EXAMPLEEXAMPLE

The data shows that The data shows that when a golf ball, tennis when a golf ball, tennis ball, and a wiffle ball ball, and a wiffle ball are dropped from the are dropped from the same height, the golf same height, the golf ball bounces highest ball bounces highest with a height of 71 cm. with a height of 71 cm. This finding does This finding does support the hypothesis.support the hypothesis.

***POINTS OF EMPHASIS******POINTS OF EMPHASIS***

Always write in a Always write in a scientific scientific manner. Don’t manner. Don’t refer to yourself by using words like I, me, refer to yourself by using words like I, me, mine, etc.mine, etc.

All amounts and measurements should All amounts and measurements should always be written in always be written in metricmetric units. units.

Multiple Multiple trialstrials increase the reliability of the increase the reliability of the results.results.

If you make a mistake, or If you make a mistake, or errorerror, you need to , you need to do the experiment again.do the experiment again.

Questions You Need to Know!!Questions You Need to Know!!

1. 1. How do I know if How do I know if my experimental my experimental question (Problem) question (Problem) is good?is good?

2.2. What are What are variables?variables?

The answer to the The answer to the question must be: question must be: TestableTestable MeasurableMeasurable RepeatableRepeatable

Characteristics in an Characteristics in an experiment that experiment that changechange or could be or could be changed.changed.

3. What is an 3. What is an independent independent variable?variable?

4.4. What is a What is a dependent dependent variable?variable?

5.5. What are What are constants?constants?

The factor that the The factor that the scientist changes scientist changes on on purposepurpose..

The factor that The factor that respondsresponds to a change in to a change in the independent the independent variable.variable.

Characteristics in an Characteristics in an experiment that are experiment that are kept kept unchangedunchanged in all in all trials.trials.

6. What is a control?6. What is a control?

7.7. What is data?What is data?

8.8. What are trials?What are trials?

A standard to which A standard to which you you comparecompare your your results.results.

Information collected Information collected during the experiment.during the experiment.

The The numbernumber of times of times an experiment is an experiment is repeated for each level repeated for each level of the independent of the independent variable.variable.

8. What are quantitative 8. What are quantitative results?results?

9. What are qualitative 9. What are qualitative results?results?

10.How should I set up my 10.How should I set up my bar graph or line bar graph or line graph?graph?

Results that can be Results that can be measured in measured in numbersnumbers..

Results that are Results that are observationsobservations or or descriptionsdescriptions..

When labeling the x and When labeling the x and y axis always label the y axis always label the x-axis (horizontal) with x-axis (horizontal) with the independent the independent variable, and label the variable, and label the y-axis (vertical) with the y-axis (vertical) with the dependent variable.dependent variable.

11. Which type of graph 11. Which type of graph should I use?should I use?

Bar GraphBar Graph: Used to : Used to show how the show how the independent variables independent variables comparecompare to each other. to each other.

Line GraphLine Graph: Used when : Used when you want to see how you want to see how continuous changes to continuous changes to the independent the independent variable affect the variable affect the dependent variable over dependent variable over time.time.

Pie GraphPie Graph: Used to : Used to illustrate numbers as a illustrate numbers as a percentagepercentage of a whole. of a whole. Not usually used in Not usually used in scientific experiments.scientific experiments.