Nature of Science Notes

1. Nature of Science Notes

2. Nature of Science • Nature of Science – • Scientific should be reliable and always changing • Science is complex • No step-by-step method will always be the answer to a question • science relies on skills: • making inferences and observations, • asking questions • analyzing data • communicating to others.

3. Observations and Inferences • Observation – Using your senses or a tool to record an event, characteristic, or behavior • Example: • Inference – a logical conclusion drawn from available evidence and prior knowledge. They often develop from observations. • Example :

4. Effective Scientific Questioning • Scientific Question– • question based on observations • identifies something you would like to learn more about by experimentation/researching /survey. • Good scientific questions will: • Be testable through experimentation, survey or research • Be based on observations • Deal with the natural world • Be genuine, something we don’t already know the answer to • [It is NOT a scientific question if it:] • Includes personal bias and opinion • Has to deal with morals and values • Deals with the supernatural • cannotbe measured

5. Processes Used by Scientists • Ask a Question (state the problem) • questionscome from observations • Example: When dropped from a height of 5 meters, will buttered toast land butter-side up or butter-side down more often? • Form a Hypothesis • Hypothesis – A detailed statement of what you expect the answer to your question to be • “Educated Guess”, prediction • Example: If dropped from a height of 5 meters, toast will land buttered side down 75% of the time.

6. Conducting Experiments • Test the Hypothesis • conduct experiments, make observations, and take surveys • Controlled Experiment – tests only one factor (variable) at a time • Variables: • Independent Variable – the factor that you change/manipulate • Dependent Variable – the factor that is being observed • Controlled Variables – the factors that remain the same/are NOT changed or manipulated • When testing the hypothesis, these are several things to consider: • Control Group (one) – nothing is tested; this acts as a baseline, i.e. what would happen in a normal situation • Experimental Groups (one or more) – variables are tested in these groups

7. Sample Experiment • Test the Hypothesis – Example of a Test • Experimental Scenario: Ms. Freeman and Ms. Dowd wanted to determine if there was a correlation between eating a nutritionally balanced breakfast and success on tests. One group of students was given a healthy breakfast and another group ate their normal breakfast before a test. They found that 7 out of 10 students who ate the healthy breakfast scored 80% or better on tests while 5 out of 10 students who ate their regular breakfast scored 80% or better on tests. • Identify the following from the above experimental scenario: • Independent Variable: ___________________________________ • Dependent Variable: ____________________________________ • Controlled Variables: ____________________________________ • Control Group: ________________________________________ • Experimental Group: ____________________________________

8. More Processes Used by Scientists • Analyze the Results • This is completed after all data from experiments has been collected • Tables and graphs are usually used in this step • Draw Conclusions • Do your results support your hypothesis? • Answer is YES repeat experiments or observations to verify results • Answer is NO  check for errors; formulate a new hypothesis • Communicate Results • Communicate results through written or oral report