Scientific Method

Scientific Method *Way to ask and answer scientific questions using observations and experiments

Scientific Method Flow Chart May require research

Observations *Done by using your senses… *WHAT YOU NOTICE Necessity is the mother of invention!

Question or Problem Often given in class. *Must be a testable question. Often sparked by curiosity or need.

Background Research *educate yourself (may include definitions) You may already have some background information

Hypothesis *prediction or educated guess about how things work based upon observation: "If _____[I do this] _____, then _____[this]_____ will happen." state your hypothesis in a way that you can easily measure, and construct it in a way to help you answer your original question. Most can be supported or refuted by experimentation or continued observation

Variables *factor, trait, or condition that can exist in differing amounts or types. three kinds of variables *The independent variable changed by the experimenter. A good experiment has only one independent variable. *Dependent variable responds to the change made to the independent variable *Controlled variables. quantities to remain constant to measure how much water flow increases when we open a faucet, it is important to make sure that the water pressure (the controlled variable) is held constant. If more than one variable is changed at one time…which caused the changes? *must be able to measure the values for each variable.

Example Hypotheses -What will happen if I open the faucet? -If I open the faucet THEN it will increase the flow of water independent variable: faucet opening size dependent variable: flow of water

-What will happen to the amount of sugar that can be dissolved in a pan if the water is heated? -If the water in the pan is heated THEN the amount of sugar that dissolves will increase Independent variable: raising the temperature of water Dependent variable: the amount of sugar that will dissolve

-What will happen to a plant if it receives fertilizer? -If a plant receives fertilizer THEN it will grow to be bigger than a plant that does not receive fertilizer Independent variable: having fertilizer Dependent variable: plant size

-What would happen when a bike rider rides through puddles if fenders are placed on their bike? -If I put fenders on a bicycle THEN the fenders will keep the rider dry when riding through puddles Independent variable having fenders Dependent variable how much water splashes on the rider

Overview of the scientific method process for experimentation used to answer questions and search for cause/effect changes to one item cause something else to vary in a predictable way.

Procedures *ordered series of steps to test whether your hypothesis can be supported or not -directions or recipe to follow -Must be a fair test by making sure that you change only one factor at a time while keeping all other conditions the same. * The more trials the more reliable your data.

Communicate Your Results *Data display *Analysis *Conclusion *****Publish, lab write-ups

Iterative process New information or thinking might cause a scientist to back up and repeat steps at any point during the process. http://www.youtube.com/watch?v=Q3Awp-3CxSU

Data Display Methods *Could include: Charts, graphs, photos, drawings, collections, video, written observations... You will often be asked to use procedural steps & design your own data charts or graphs for labs. Make your drawings at least three lines high. Title your data.

Analysis *relationship between data and the purpose of the experiment *What happened? Why did it happen? *patterns/trends shown in your data *Your lab may not have worked. Explain here. Should be a few paragraphs discussing lab.

Conclusion: *Answer the problem you started your lab with. Was your hypothesis supported or refuted by your experiment? *Provide and discuss the best evidence you collected that supports the hypothesis. if the hypothesis was not supported by the experiment, construct a new hypothesis starting the entire process of the scientific method over again. Your data can support or reject the hypothesis but CANNOTprove it with one lab

Scientific Theory “just a theory,” usually means a mere guess, or unproved thought *implies something has been proven and is generally accepted as being true multiple times by different groups of researchers.. explains an entire group of related phenomena *Examples: theory of evolution, the theory of relativity, the atomic theory, and the theory of plate tectonics.

Scientific Law *statement of fact to concisely describe, an action or set of actions. *have always been observed to be true *Examples: the law of gravity, Newton's laws of motion, the laws of thermodynamics, Boyle's law of gases, and the law of conservation of mass and energy

Using the SCIENTIFIC METHOD It’s all about problem solving. Finding a date for the Sadie Hawkins Dance.

STEP 1: State the PROBLEM * You cannot solve a problem until you know exactly what it is. • Problem: What will happen if I ask **** to the Sadie Hawkins Dance Friday night?

STEP 2: RESEARCH the problem. What will it take to solve my problem? What do I know, and need to know, about my problem?  OBSERVATIONS: Who can I take? * Examine the possibilities * Eliminate poor choices * Consider likely choices

STEP 3: Form a HYPOTHESIS. • Hypothesis: • an educated guess to the solution of your problem. If I ask *** to the Sadie Hawkins Dance then I will have a date.

STEP 4: TEST the hypothesis. Perform an EXPERIMENT to test your hypothesis.  Ask (___NAME___) out for a date.

STEP 5: ANALYZE results. • Data are the results of the experiment. • How do you interpret the data? • What does it mean if . . . they say nothing? • What does it mean if . . . ignore me? • What does it mean if . . . they just smile? • What does it mean if . . . they run?

STEP 6: Draw CONCLUSIONS. • In its simplest form there are only two possible conclusions: • If your hypothesis was correct, you now have a date!  PROBLEM SOLVED—YIPPEE! • If your hypothesis was incorrect, then you learned through the process that you will need to reconsider: * Did you make a poor selection? * Was your experiment flawed? * What was wrong with your original hypothesis?  FORM ANOTHER HYPOTHESIS AND TEST IT.

Required Definitions: • Control –used as a standard for comparison, what is kept constant • Data – Information, measurements and materials gathered from observations • Experimental error – Incorrect data • Experiment –using observations and controlled variables to discover answers to questions, and/or to check a hypothesis.

Required Definitions • Hypothesis – testable explanation for observations and questions • Observation – noticing objects or events using senses. *Qualitative data – observable characteristics of things or events collected using senses. Example: “The juice tastes sweet to me.” *Quantitative data – Data based on measurable characteristics using numbers.

Required Definitions • Repeated trials – tests done more than once. • Replication – Repeated trials on more than one subject • Scientific law – generalized pattern in nature • Scientific theory – explanation for generalized patterns in nature that is supported by much scientific evidence based on data collected using scientific methods. • Variation – Slight differences

Required Definitions • Variable – factor that may change in an experiment. • Variable, independent – factor that can be changed or manipulated in an experiment, variables you can change. • Variable, dependent – factor that responds to changes in other variables in an experiment, variables that respond to the one you changed

Scientific Method