THE NATURE OF SCIENCE AND SCIENTIFIC METHODS What is Science? How is Science Done?

SCIENCE IS: a way of understanding the natural world based on our senses and instruments to enhance our senses exploration http://pirun.ku.ac.th/~fscinpc/

CHARACTERISTICS OF SCIENCE tentative: subject to change empirical: measurable in terms of real data logical: organized and explanative objective: based on supportive evidence social: communicated among scientific community creative: imaginative, fun, and useful (TECHNOLOGY is the practical application of science) http://www.mathiaspedersen.com/3dportfolio/highres/poor_pluto_1600x900.jpg BIG IDEA: Science seeks to CREATE NEW KNOWLEDGE Pluto is no longer considered a planet – more information and further refinement of definition of planet….. CLASSIFICATIONS may change because there are more facts FACTS DO NOT CHANGE!!

SCIENCE ASKS: What’s there? How does it work? How did it come to be this way? http://pirun.ku.ac.th/~fscinpc/

SCIENCE IS DONE by EVERYONE, EVERYDAY to develop new knowledge using the SCIENTIFIC METHOD as a way to collect data (general process) to answer a question

SCIENTIFIC METHOD Many expressions of the scientific method!!! ALL start with OBSERVATION information gathered from the senses After observation, steps do not have to be done “in order” ALL “end” with sharing information & starting over http://www.thwink.org/sustain/deadlock/WhyUnableToSolveProblem.htm ALL involve Identifying a problem & forming an explanation (hypothesis/prediction) testing the explanation (experimenting) gathering data & results (organizing data) drawing conclusion & communicating them

this information is condensed into the purpose OBSERVATION Why is it that way? What do other people know about this? How can I find out more? this information is condensed into the purpose informal lab report this information becomes the Introduction formal lab report

INFERENCE? HYPOTHESIS? OR PREDICTION? an explanation based on evidence and reasoning an explanation based on evidence and reasoning a guess at what will happen based on prior experience INFERENCE a testable explanation that guides an experiment PREDICTION HYPOTHESIS

Test hypothesis under controlled conditions An Example http://www.agronext.iastate.edu/corn/production/management/cropping/cornfollowcorn.html OBSERVATION Some plants are taller than others Reading says soybeans act as fertilizer PROMPT: WANT TO TEST FERTILIZER CONTROL: NO FERTILIZER EXP GROUP: FERTILIZER HYPOTHESIS Corn with fertilizer will grow taller than corn without fertilizer EXPERIMENT Test hypothesis under controlled conditions

receives independent variable receives “normal” treatment DESIGN AN EXPERIMENT A controlled experiment is a comparison of two or more groups with one difference between the groups EXPERIMENTAL GROUP receives independent variable CONTROL GROUP receives “normal” treatment Corn will receive: sunlight water soil Corn will receive: sunlight water soil fertilizer PROMPT: WANT TO TEST FERTILIZER CONTROL: NO FERTILIZER EXP GROUP: FERTILIZER SAMPLE GROUP: Smaller group representative of population (example – political polls)

VARIBLES: Factors that can change sunlight, water, soil CONSTANT VARIABLE: factors that stay the same fertilizer INDEPENDENT VARIABLE: the difference between the groups; the factor manipulated (changed) by the experimenter INDPEPENDENT: FERTILIZER DEPENDENT: PLANT HEIGHT DEPENDENT VARIABLE: the measured result of the experiment; the factor that responds to the change plant height

Experiment & Collect Data DATA / EVIDENCE: “raw” or unprocessed measurements from the experiment QUALITATIVE: (subjective): descriptive data, uses words, pictures QUANTITATIVE: (objective): numerical data, from instruments Height of corn with fertilizer was taller than control group QUALITATITVE: taller, bigger, short, no growth QUANTITATIVE: any numerical change like 2cm taller, 0 cm growth Height of corn with fertilizer averaged 2 cm taller than control group

RESULTS & ANALYSIS What does your data mean? RESULTS: evidence from experiment; organization of data Tables, graphs, visual representation of data This is to be very objective – no commentary

CONCLUSIONS (TELL) Make a CONCLUSION (explanation based on data) Does the data support or refute the hypothesis? Were there any ERRORS (sources of mistakes)? Was there a way to improve the experiment? Conclusions – now commentary OK

WHAT NOW???? After several experiments have been done, Scientists SHARE their findings and/or develop… MODEL: graphical explanation or representation THEORY: a well-tested hypothesis that is has not been proven wrong; generally accepted to be “correct,” unless disproven LAW: a predictable relationship that is accepted as fact; often expressed as a formula (F=ma) PRINCIPLE: a concept from which other ideas are derived MODEL: ATOMIC STRUCTURE THEORY: EVOLUTION LAW – usually means formula; PRINCIPLES – usually more general LAW/Principle often used interchangeably BIG IDEA: CREATE NEW KNOWLEDGE AND TELL OTHERS

OVERVIEW OF S.M. Tests explanations Refines ideas Tests them again Shares what happened http://www.sciencebuddies.org/science-fair-projects/project_scientific_method.shtm

References http://www.a2zteachersoutlet.com/images/cwg3503.gif Various ideas/pictures from Integrated Science Team at Palisades Charter High School