The Scientific Method

What it is: Techniques for: Investigating phenomena Acquiring new knowledge Correcting and integrating “old” knowledge

What makes it scientific: In order for conclusions reached by using the Scientific Method to be valid the following must be true: Data has been gathered that is observable, measurable and fair (empirical) Data comes from observation and/or experimentation

A hypothesis has been formed A hypothesis has been tested

How to use the Scientific Method Procedures vary from one field of science to another but all follow a basic pattern First the scientific researcher will propose a hypothesis Then an experiment must be designed to test the hypothesis

When an experiment is created it must have steps that can be repeated so that when it is done again by somebody else the results can be predicted

Hypothesis vs Theory Hypothesis: A suggested explanation for something that has been observed Ex: Observation: My car seat is wet and my window was left down Hypothesis:

Theory: An explanation that has been well tested and confirmed as a general principle helping to explain and predict a wide range of similar future events. A theory can still be proven wrong with enough data Ex: The Expanding Earth Theory

The Expanding Earth Theory The Theory: The Earth is continually getting larger, which is why the continents are moving, new mountains are formed and why sometimes it feels like the earth is moving (up to the early 1900’s) Disproven By: Discovery of plate tectonics, pictures from space, continental drift theory etc.

The Steps of the Scientific Method Define the question Gather information and resources (observe) Form an hypothesis Perform experiments & collect data Analyze data Interpret data Draw conclusions Publish results

The Experimental Method Five steps that must be done when doing an experiment Sometimes the order of the steps changes Sometimes a step may be left out It is always possible to go back and do a step again

Step 1: Observe An interesting natural phenomenon or a problem that needs a solution These observations are made using your five senses and instruments to extend your senses, like a microscope There are two kinds of observations: quantitative and qualitative

Quantitative vs Qualitative Quantitative: an observation involving quantities that can be expressed in numbers Qualitative: an observation that involves quality, shape or properties that cannot be expressed in numbers

Step 2: Develop a Research Question Observations can raise questions When a prediction is made about the answers to these questions this becomes the hypothesis A hypothesis can be proven or disproven Ex: Question: Does dark clothing or light clothing get hotter in the sun? Hypothesis: “Clothing that is dark will get hotter than light clothing.”

Rules for a hypothesis NO PERSONAL PRONOUNS!!! Full sentence(s) Must have a definite, specific prediction Ex: “The temperature will increase” NOT “The temperature will change”

Step 3: Define the Variables Variable: Something that can vary or change What will be controlled or monitored during the experiment

Step 4: Experiment List the steps of the experiment as a procedure that is clear enough for someone else to do the experiment exactly the same

Requirements for a Procedure To write an experimental procedure properly you must: Choose the equipment and material you need b) Prepare step-by-step instructions that are clearly numbered at each step (remember lab safety)

c) Use all the equipment on the list d) Monitor the variables you have selected e) Conduct the experiment following the safety rules f) Record all the information you collect

Step 5: Analyze and Present the Results Results must be organized and presented appropriately Results must include all observations and calculated values When analyzing your results you must remember to answer the initial question

If the experiment was appropriate for the question(s) your were trying to answer you should be able to draw conclusions (answers) This is also where you state any possible errors that occurred or what you would do differently the next time In the conclusion there are again NO PERSONAL PRONOUNS