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 17 th 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 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. manipulated variableThe one thing you change is called the manipulated variable. controls.All the things you keep the same are called controls. responding variableThe result of each trial is called the responding variable

Galileo’s Experiment manipulated variableWhat was the manipulated variable in Galileo’s experiment? The weight of the balls. controlsWhat were some controls? 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.

Review

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.