The Nature of Science and Technology Chapter One Section 2 Scientific Inquiry

Scientific Inquiry Scientific inquiry refers to the diverse ways in which scientists study the natural world and propose explanations based on the evidence they gather. For example, if you have ever wondered why an item is not working then you are using scientific inquiry (i.e. remote control, mechanical pencil, etc.)

SCIENTIFIC INQUIRY Posing Questions Developing a Hypothesis Designing an Experiment Collecting and Interpreting Data Drawing Conclusions Communicating Scientific Theories and Laws

1. Posing Questions Scientific inquiry often begins with a problem or question about an observation. Questions often arise from experiences or observations. Which of the following questions can be answered using scientific inquiry? Which brand of running shoe looks best? Does running make your muscles stronger than swimming does?

2. Developing a Hypothesis A hypothesis is a possible explanation for a set of observations or answer to a scientific question. A hypothesis is NOT a fact. Instead, it is only one possible way to explain a group of observations. In science, a hypothesis must be testable!

3. Designing an Experiment Controlling Variables Setting Up a Controlled Experiment The Importance of Controlling Variables Forming Operational Definitions

Controlling Variables Variables are factors that can change in an experiment. Manipulated or independent variable is the one variable that is purposely changed to test a hypothesis. Responding or dependent variable is the factor that may change in response to the manipulated variable.

Setting Up a Controlled Experiment Controlled experiment is an experiment in which one variable is manipulated at a time.

The Importance of Controlling Variables What happens to the hypothesis if the variables are not controlled?

Forming Operational Definitions An operational definition is a statement that describes how to measure a particular variable or define a particular term.

4. COLLECTING and INTERPRETING DATA Organizing Your Data Graphing Your Results

Organizing Your Data Data are facts, figures, and other evidence gathered through observations. A data table provides you with an organized way to collect and record your observations.

Graphing Your Results After your data has been collected, they need to be interpreted. One useful tool that can help you interpret data is a graph. Graphs can reveal patterns or trends in data.

5. DRAWING CONCLUSIONS A conclusion is a summary of what you learned from an experiment. In drawing your conclusion, you should ask yourself whether the data supports the hypothesis. You also need to consider whether you collected enough data. Inquiry Leads to Inquiry The Nature of Inquiry

Inquiry Leads to Inquiry Scientific inquiry usually doesn’t end once a set of experiments is done. Often, one scientific inquiry leads into another one!

The Nature of Inquiry Scientific inquiry is a process with many paths, not a rigid sequence of steps. Often, a surprising observation or accidental discovery leads into inquiry.

Examples of Accidental Inventions Discovery of the principle behind inkjet printers by a Canon engineer. After putting his hot soldering iron by accident on his pen, ink was ejected from the pen's point a few moments later. Vulcanization of rubber, by Charles Goodyear. He accidentally left a piece of rubber mixture with sulfur on a hot plate, and produced vulcanized rubber Safety glass, by French scientist Edouard Benedictus. In 1903 he accidentally knocked a glass flask to the floor and observed that the broken pieces were held together by a liquid plastic that had evaporated and formed a thin film inside the flask. Corn flakes and wheat flakes (Wheaties) were accidentally discovered by the Kelloggs brothers in 1898, when they left cooked wheat untended for a day and tried to roll the mass, obtaining a flaky material instead of a sheet.

More Examples of Accidental Inventions The microwave oven was invented by Percy Spencer while testing a magnetron for radar sets at Raytheon, he noticed that a peanut candy bar in his pocket had melted when exposed to radar waves. Pyroceramic (used to make Corningware, among other things) was invented by S. Donald Stookey, a chemist working for the Corning company, who noticed crystallization in an improperly cooled batch of tinted glass. The Slinky was invented by US Navy engineer Richard T. James after he accidentally knocked a torsion spring off his work table and observed its unique motion. Art Fry happened to attend a 3M college's seminar on a new "low-tack" adhesive and, wanting to anchor his bookmarks in his hymnal at church, went on to invent Post-It Notes. The chocolate chip cookie was invented through serendipity Chocolate chip cookies were invented by Ruth Wakefield when she attempted to make chocolate drop cookies. She did not have the required chocolate so she broke up a candy bar and placed the chunks into the cookie mix. These chunks later morphed into what is now known as chocolate chips.

6. COMMUNICATING Communicating is the sharing of ideas and experimental findings with others through writing and speaking. Scientists share their ideas in many ways. For example, they give talks at scientific meetings, exchange information on the Internet, or publish articles in scientific journals.

7. SCIENTIFIC THEORIES and LAWS Scientific Laws

SCIENTIFIC THEORIES A scientific theory is a well-tested explanation for a wide range of observations or experimental results. For example, today, scientists know that Earth, along with the other planets in the solar system, revolves around the sun. Scientists accept a theory only when there is a large body of evidence that supports it.

SCIENTIFIC LAWS A scientific law is a statement that describes what scientists expect to happen every time under a particular set of conditions. Unlike a theory, a scientific law describes an observed pattern in nature without attempting to explain it. You might think of a scientific law as a rule of nature.