scientific process (formerly the scientific method)

Scientific Process(formerly the scientific method)

Beginnings

• Aristotle (384 BCE-322 BCE or BC)• ancient Greek philosopher

Aristotle• Aristotle, more than any other thinker, determined the

orientation and the content of Western intellectual history. He was the author of a philosophical and scientific system that through the centuries became the support and vehicle for both medieval Christian and Islamic scholastic thought: until the end of the 17th century, Western culture was Aristotelian. And, even after the intellectual revolutions of centuries to follow, Aristotelian concepts and ideas remained embedded in Western thinking.

• In other words, Aristotle was so famous that his work influenced thinking in the Western world from his time to the present.

• This was fine when he was right. But he was so influential that his mistakes were never noticed.

• Aristotle and his contemporaries believed that all problems could be solved by thinking about them.

• Sometimes this worked, other times it did not.

• For example, Aristotle thought that heavy objects would fall faster than lighter ones.

• Now that does seem reasonable at first. And this is how “science” was done in ancient times.

• But what did Aristotle not do?• He never tested his ideas!• The world would have to wait

almost 2000 years for that to happen.

Galileo Galilei•1564-1642 AD or CE

•Lived in what is today Italy

•Is considered to be the first true scientist.

•Why????

•Because he actually did the experiment.

• Aristotle said that heavy objects fall faster than lighter ones.

• So Galileo asked, “How much faster?”• So he sent students up to the top of a

building and had them drop a heavy ball and a lighter one off at the same time. He had other students waiting below to measure the difference in time between the two hitting the ground.

• Today of course we know what happened. Much to everyone’s surprise both balls hit the ground at about the same time!

• This shows that it is much preferred to test your ideas rather than merely think about them.

• One test is worth a thousand expert opinions. Bill Nye

Key Ideas• When conducting an experiment,

change one factor and keep everything else exactly the same.

• The one thing you change is called the manipulated variablemanipulated variable.

• All the things you keep the same are called controlscontrols..

• The result of each trial is called the responding variableresponding variable

Galileo’s Experiment

• What was the manipulated manipulated variablevariable in Galileo’s experiment?

• The weight of the balls.• What were some controlscontrols?• Dropped from same height.• Dropped at same time.• Balls had same shape/size.

Responding Variable

• What was the responding variable in Galileo’s experiment???

• When the balls hit the ground.

ReviewVariable: theone thing youchange in anexperiment.

Data: theinformation youget when youtest thevariable.

Controls: theparts of theexperiment thatstay the same.

Manipulatedvariable: youchange thisyourself.

Respondingvariable:responds to thechange youmade.

Controllingvariables

I ndependentvariable: on itsown.

Dependantvariable:depends on thechange youmade.

Controllingvariables

Scientific Method Steps

• State the problem.• Make a hypothesis.• Conduct the experiment.• Record/analyze data.• Make a conclusion.• Report findings to others so they

can repeat the experiment.

Hypothesis

• An educated guess• a prediction• Use “If”, “then” format• We predict that if we drop a ball from

a higher height, then it will bounce higher.

• “If” is the manipulated variable.• “Then” is the responding variable.

Observations

• Observations: We use our senses to gather information about the world around us. There are two types of observations.

Qualitative• Qualitative observation: (quality)

Usually made with our senses. • Color, shape, feel, taste, sound.• Olivia is wearing a blue sweater.• The lab tabletop is smooth.• The dog’s fur is shiny.

Quantitative•Quantitative observation: (quantity)

How many. Will always have a number.

•Based on exact measurement.•The room is 8 meters across.•Sarah is 141-cm tall.•Sam weighs 450

Newtons.

Inferences

• Inference:• A logical interpretation of an event

that is based on observations and prior knowledge.

• What does this mean in 6th grade terms?

Making Inferences

• You are at the counter in the office to get a bus pass signed. You see a student leave the principal’s office crying and upset. We could make an inference as to why the student is upset.

• Could be in trouble (ISS, OSS, expelled)• Family problems at home (sick, accident)• Student not feeling well• Student has poor grades (failing, retention)

Graphing

• Graphs are a useful tool in science.

• The visual characteristics of a graph make trends in data easy to see.

• One of the most valuable uses for graphs is to "predict" data that is not measured on the graph.

Graphing Steps

• Identify the Variables• Determine the range• Determine the scale• Number and label

each axis• Plot the points• Draw the graph• Give your graph a title

Identify the Variables

– Manipulated Variable - (the thing you changed)

Goes on the X axis (horizontal) Should be on the left side of a data

table.

– Responding Variable - (changes with the independent variable)

Goes on the Y axis (vertical) Should be on the right side of a data

table.