The Nature of Science Defining Science Problem-Solving Scientific Method Experimental Design 1

Defining Science Science is a process of observations and investigations through which information about the natural world is learned. It is both the process of gaining knowledge and the resulting body of knowledge 2

Defining Science Pure Science research that adds to the body of scientific knowledge “has no practical use” Applied Science (Technology) the practical application of scientific knowledge 3

Defining Science Pure human genetics polymer science atomic theory study of the human ear Applied DNA fingerprinting Under Armor nuclear weapons hearing aids 4

Let’s see what you know about science… Science Geology Physical Science Social science Plastics Matter Physics Chemistry Astronomy Meteorology/Weather Minerals Energy Drugs Acid rain Earthquakes Stars Art Flight Clouds Black holes Electricity Tornados Religion Math

Categories of Science Life Science the study of living organisms Earth Science the study of Earth and space Physical Science the study of matter and energy chemistry & physics WHAT ELSE CAN SCIENCE DO? 6

Solve Problems “ I would spend fifty-five minutes defining the problem and only five minutes finding the solution. ”

Problem-Solving 1.Identify the problem. What do you know? Observation? Patterns? What do you need to know? Ask Questions 2.Plan a strategy. Use what you know to predict a solution or solutions. Design an experiment Develop a model 8

Problem-Solving 3.Execute your plan. Run your experiment Gather Data 4.Evaluate your results. Did you solve the problem? Is your answer reasonable? Identify - Plan - Execute - Evaluate 9

Scientific Method 1.Determine the problem. 2.Make a hypothesis. 3.Design your Experiment 4.Present your Results 5.Draw conclusions. 10

Scientific Method 1.Determine the problem. Observe Ask questions 2.Make a hypothesis.Make a hypothesis. IF / THEN “BECAUSE” A Testable Statement 3.Design Your ExperimentDesign Your Experiment How could we test our hypothesis? What data are you going to collect? 4.Present the results. What happened during our test? Graphs/Tables 5.Draw conclusions.Draw conclusions. Was our hypothesis supported? Is further testing necessary? 11

Designing your Experiment Experiment Organized procedure for testing a hypothesis Key Components: Control - standard for comparison Single variable - keep other factors constant Repeated trials - for reliability 12

Designing your Experiment Types of Variables Independent Variable adjusted by the experimenter what you vary Dependent Variable changes in response to the independent variable what you measure Constant Variable Variable that could be changed but are deliberately held constant 13

Theories and Laws Hypothesis – A testable statement Theory - explanation of “why” based on many observations & experimental results Scientific Law - prediction of “what” describes a pattern in nature Example: LAW OF CONSERVATION OF MASS 14

Scientific Method Theories and laws are well-accepted by scientists, but... They are revised when new information is discovered. THEY ARE NOT SET IN STONE! 15

YOU TRY You are in charge of increasing the popping efficiency at the local movies theater. By doing so not only will you increase the company’s profit margin but you will also get a raise if you succeed. After some research you have found that some people have had success by freezing the kernels before popping IF the popcorn is stored in the freezer THEN it will pop better. 16 IF popcorn popping efficiency is related to temperature, THEN freezing the kernels before popping will yield fewer un-popped kernels. Develop A Hypothesis:

Freezing Corn Single variable: Storage temperature Constants: Popcorn brand Freshness Storage time Popper Independent Variable: Storage temperature Dependent Variable: Number of un-popped kernels 17

Freezing Corn Single variable: Storage temperature Constants: Popcorn brand Freshness Storage time Popper Independent Variable: Storage temperature Dependent Variable: Number of un-popped kernels 18