1-2 Scientific Inquiry How do scientists investigate the natural world? What role do models, theories, and laws play in science?

What is Scientific Inquiry? Scientific Inquiry refers to the different ways scientist study the natural world. It is the ongoing process of discovery in Science. In the process of scientific discovery, scientists use curiosity, honesty, open-mindedness, skepticism, and creativity. Why are these good qualities for a scientist to have?

Process of Inquiry Includes: Posing questions Developing hypotheses Designing experiments Collecting and interpreting data Drawing conclusions Communicating ideas and results

The Nature of Inquiry There is no set path that a scientific inquiry must follow. Different scientists may choose different paths when studying the same event. Chapter 1 Introduction to Physical Science

The Scientific Method  The scientific method is a more linear, organized way to inquire about science.  It always starts with an observation.  Copy the flow chart to the left, but add a bubble to the top that says “Make Observations.”

Step #1: Observations Observations lead to a question or problem Example: You enter a dark room and you observe that the lights are not turning on. This should lead you to the Question (Step #2) “Why are the lights not working?”

Step #3: Background Research Research will help you form a hypothesis that makes sense. You could use the internet, books, or even talk to knowledgeable people to see what could be possibly causing the lights to not turn on. Example: Possible explanations you come up with could be that the light bulb burnt out, or the electrical outlet is not working, or the breaker needs flipped, etc… Who can think of some other possible explanations?

Step #4: Hypothesis Form a hypothesis (possible explanation for observations) -Use the research you just did! -Understand that your hypothesis is only ONE possible explanation, and may not be correct! Example: You hypothesize that the light bulb has burnt out.

Step #5: Test the Hypothesis with an Experiment Collect data through observation or measurement Qualitative: characteristics (ex: red hair) Quantitative: numbers (ex: plant height= 32cm) Example: Check other known-working light bulbs in the lamp to see if the light will turn on.

Controlled Experiments… only 1 thing ( called a variable) changes *Variable that is deliberately changed= manipulated variable (independent variable) -What is the independent variable in this experiment? (Hint: What are we changing?) *Variable that is observed and changes in response= responding variable (dependent variable) -What is the dependent variable in this experiment? (Hint: What is changing because of our independent variable?) THE LIGHT BULB! WHETHER OR NOT THE LIGHT TURNS ON!

Controlled Experiments… *All other variables in the experiment are held constant, which means they never change= controlled variable (constant variable) -What are some of the controlled variables in this experiment? *Why would a Scientist want to use a controlled experiment? THE LAMP, THE ROOM, THE ELECTICAL OUTLET

Step #6 (Part I): Record & Analyze Data Organize your data into charts and graphs so that it is easier to recognize patterns Example: Light bulb #1Light bulb #2Light bulb #3Light bulb #4 NOT WORKING

Step #5: Draw Conclusions Decide if the evidence supports or rejects your hypothesis. Example: All light bulbs in that lamp, plugged into the same outlet are not functioning, therefore I will reject my initial hypothesis because it is unlikely that all light bulbs are burnt out. Rejecting your original hypothesis is valid information because it helps you rule out possible causes to the problem or question and allows you to make a new hypothesis and start the steps of the scientific method over again.

 Since our Hypothesis was not correct, we will go back to step #4 and form another hypothesis that we can test…. ANY IDEAS???  After we form our new hypothesis, we will go back through the steps of the scientific method!  Once we find a hypothesis that is correct, we have answered our question!  In larger experiments, scientists will write up lab reports, repeat their experiments, publish their results, or even branch out from the experiment to test other ideas.

Why would scientists want to write lab reports and/or publish their results? So other scientists can learn from their data, and to possibly receive credit for their work. Why would scientists want to repeat their experiments? To make sure their results are accurate.

When does a hypothesis become a theory? When a hypothesis is tested and confirmed enough times that it is unlikely to be proven wrong by future tests In science, the word theory applies to a well- tested explanation that brings together a lot of observations A theory may be changed or replaced as new evidence is discovered

What is a Law? A law is a statement that describes what scientist expect to happen every time under a particular set of conditions. It describes an observed pattern without attempting to explain it. Laws have been verified over and over again. Example: The Law of Gravity- states that all objects in the universe attract each other.

Theories Versus Laws: Theories EXPLAIN! Laws DESCRIBE!