Chapter 1 Section 2: Scientific Inquiry Key Concepts Responding variable Controlled experiment How do scientists investigate the natural world? Data Communicating What role do models, laws, and theories play in science? Scientific law Scientific theory Key Terms Scientific inquiry Hypothesis Variable Manipulated variable

Socratic Method – Quick Review! What 3 skills do scientists use? What are the 2 main branches of physical science? How does a photographer, piano tuner, or firefighter use physical science? What is predicting?

The Steps to Scientific Inquiry Scientific inquiry refers to the different ways scientists study the natural world. The steps of scientific inquiry are: Posing questions Developing hypotheses Designing an experiment Collecting and interpreting data Drawing conclusions Communicating results

Examples of the steps Pose questions Develop hypotheses Do younger drivers get more speeding tickets? Do taller people hit their heads more often? Are trout more likely to get parasites in shallow and warmer water? Develop hypotheses Hypothesis – a possible answer to a scientific question or an explanation for a set of observations. A hypothesis is NOT a fact. A hypothesis MUST BE TESTABLE by experiment or observation.

Design an experiment Collect and interpret data (facts, figures, and other evidence gathered through observations) Examples: Collect ages and # of tickets and plot them on a graph (do young people get more speeding tickets?) Collect height and number of head bumps in the past week and plot them on a graph (do taller people hit their heads more often?) Test trout living in shallow warm water vs. trout living in deeper colder water (are trout more likely to get parasites in shallow warm water?) Draw conclusions What did you experiment results indicate? Communicate results

Let’s write the steps in our ISN It is important to understand the steps and their order. Let’s list the steps in our ISNs on the right side of the page On the left side, we will draw the figure from page 14 together. Why is “pose questions” at the center of the process? Would a scientist be wrong to discontinue a long-running experiment before it was completed in order to pursue another direction?

Variables, Experiments, and Data Data are the facts, figures, and other evidence gathered through observations QUANTITATIVE DATA IS OFTEN MEASURED IN THE INTERNATIONAL SYSTEM OF UNITS (SI). Variables are factors that can change in an experiment. Manipulated Variables The variable that is changed. It is also known as the independent variable. Responding Variables The variable that is expected to change because of the manipulated variable. Controlled experiment – an investigation in which all variables except one remain the same. Communicating – sharing ideas and conclusions with others through writing and speaking

How science develops Scientific models A representation of an object or process Can you think of a time a model would be useful to a scientist? Maps, globes, simulations….?

Super important… Scientific laws Scientific theories A statement that describes what scientists expect to happen every time a under a particular set of conditions. Like a rule of nature Example: law of gravity (?) Gravity has both a law and a theory What is another scientific law? Scientific theories A well-tested explanation for a wide range of observations or experimental results. Example: atomic theory What is another scientific theory?

Theory or law? Remember: A scientific theory is NOT the same as the colloquial (defined: ordinary or common language) definition of a theory. In science, a theory is a well-substantiated explanation of some aspect of the natural world that can incorporate facts, laws, inferences, and tested hypotheses. In science, a law is a descriptive generalization about how some aspect of the natural world behaves under stated circumstances. It can often be reduced to a mathematical equation. Example: e= mc2

Practice questions! What is the study of matter and energy called? What is the study of the properties of matter and how matter changes called? What is an experiment in which only one variable is manipulated at a time called? What is the main characteristic of a scientific law? What is the main characteristic of a scientific theory? WRITE THESE DOWN IN YOUR ISN AND ANSWER THEM. THIS IS YOUR HOMEWORK FOR TOMORROW.