The Scientific Method

The Skeptical Chemist Robert Boyle In “The Sceptical Chymist” scientific speculation Boyle stated that scientific speculation was worthless unless it was supported experimental evidence by experimental evidence. scientific method This principle led to the development of the scientific method. (1661)

Scientific Method is a way to solve problems. Do you have any problems to solve? Any big or any small ones?

Parts of the Scientific Method Identify a problem. Research the problem Make a hypothesishypothesis (a testable prediction). Experiment to testExperiment the hypothesis. Draw a valid conclusion.

Hypotheses A tentative explanation for the observations When you turn the ignition key, you hear a rapid clicking sound, and the dash lights dim. Hypothesis may not be correct, but it puts your understanding of the system being studied into a form that can be tested. If ________ then ______ because

Make observation My car will not start Make observation My car will not start Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8 Scientific Method Research Look in Books, ask neighbors, go on line Car is out of gas Battery is dead Bad alternator Bad solonoid Research Look in Books, ask neighbors, go on line Car is out of gas Battery is dead Bad alternator Bad solonoid Develop hypothesis If the battery is DEAD then the car will not start because there is no electricity Develop hypothesis If the battery is DEAD then the car will not start because there is no electricity

A Scientific Experiment procedure the order of events in an experiment; the “recipe” Experiments must be controlled; they must have two set-ups that must differ by only one variable. The conclusion must be based on the data. variable any factor that could influence the result

Data Observations are also called data. There are two types of data. qualitative dataquantitative data descriptions; measurements; no numbersmust have numbers and UNITS

Identify the Qualitative and Quantitative Data Car lights dim when the battery is low The battery produces 12 volts dc The gas tank contains 5 gallons of gas The green apples are acidic. The solution contains 4 grams of sugar The high frequency sound damages ears High Brass contains at least 65% zinc

Make observation Research Develop hypothesis Develop hypothesis Test hypothesis with an experiment Replace battery Attempt to start the car Test hypothesis with an experiment Replace battery Attempt to start the car Analyze data and draw Conclusions Car did not start Analyze data and draw Conclusions Car did not start Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8 Scientific Method Hypothesis is NOT supported Hypothesis is NOT supported Revise hypothesis Revise hypothesis

Make observation Research If we replace the alternator then it will start because it will convert mechanical energy to electrical energy If we replace the alternator then it will start because it will convert mechanical energy to electrical energy Test hypothesis with an experiment Replace the alternator Attempt to start the car Test hypothesis with an experiment Replace the alternator Attempt to start the car Analyze data and draw Conclusions Car starts Analyze data and draw Conclusions Car starts Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8 Scientific Method Hypothesis IS supported Hypothesis IS supported Test hypothesis with further experiments Test hypothesis with further experiments

Make observation Ask question Develop hypothesis Develop hypothesis Test hypothesis with an experiment Test hypothesis with an experiment Analyze data and draw conclusions Analyze data and draw conclusions Hypothesis IS supported Hypothesis IS supported Hypothesis is NOT supported Hypothesis is NOT supported Develop theory Develop theory Test hypothesis with further experiments Test hypothesis with further experiments Revise hypothesis Revise hypothesis Wysession, Frank, Yancopoulos, Physical Science Concepts in Action, 2004, page 8 Scientific Method

Everyday Science Scientific MethodMaking Spaghetti Sauce ObservationSpaghetti sauce should be red. Hypothesis (prediction) If I use tomato sauce it will be red. TestHeat pot of tomato sauce. Observe resultTaste the sauce - bland. Revise hypothesis?If I add garlic to tomato sauce it will not be bland New test?Add garlic, taste - not so bland. ConclusionThe Final Recipe.

Then And Question Research Hypothesis Procedure/ Method Procedure/ Method Data Observations Conclusion What does the scientist want to learn more about? What does the scientist want to learn more about? Gathering of information An “Educated” guess of an answer to the question An “Educated” guess of an answer to the question Written and carefully followed step-by-step experiment designed to test the hypothesis Written and carefully followed step-by-step experiment designed to test the hypothesis Information collected during the experiment Information collected during the experiment Written description of what was noticed during the experiment Written description of what was noticed during the experiment Was the hypothesis correct or incorrect? Was the hypothesis correct or incorrect? Next Then Next And Finally First Scientific Method A Review

An Apple a Day Keeps the Doctor Away

Does and an apple a day keep you healthy? Hypothesis If you eat an apple a day then you will be healthy because apples contain vitamins that help the body fight diseases. Experiment Have two very large groups of people testing. One group eats an apple a day the other does not eat apples. Data Track the health of each group for an extended period. Conclusion

An Apple a Day Keeps the Doctor Away From the side of your bed if aimed at his head

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Scientific Method V0_PTc

SCIENTIFIC METHOD How do scientists do what they do? Well, YOU know because you're a scientist, too! Observation is an important part-- in fact it's the part at the very start. For it's observation that causes you to wonder why earthworms do what they do and clouds form in the sky.

SCIENTIFIC METHOD Your hypothesis is a "best guess" based on what you know about how things work--now you're ready to go! Experimentation lets you test the hypothesis you've made-- to see if your best guess can make the grade. And because variation is found in nature everywhere

SCIENTIFIC METHOD repeated trials should be done, and done with care. And don't forget to decide what variables you'll test. You change the independent variables, but not the rest. Recording your data is very important, too; so you can analyze the results and others can repeat what you do

SCIENTIFIC METHOD When you've summarized your results and your experiment is done, you'll have more information about nature and you'll have had some fun. So, now you know that the scientific method is really cool, and that scientists don't just measure--they RULE!

The Scientific Attitude The Scientific Attitude

“This attitude is one of inquiry, experimentation, honesty, and a faith that all natural phenomena can be explained.”