Def: A process to gain knowledge through thought, experience, and proof of results

The 5 basic steps of Scientific Method : 1.Question 2.Hypothesis 3.Experiment 4.Collect and Analyze Data 5.Conclusion

Terms and definitions Hypothesis: an educated guess about the solution to a problem Can be tested by an experiment Is formed when you only know a little about what is going to happen Experiment: studying the effect of one thing on another to test a hypothesis Conclusion: a judgment based on the results of an experiment

Terms and definitions Variable: a factor that affects the result of an experiment Independent variable: the variable that causes change, “Parent variable” Dependent variable: the variable being changed. Data collected. “Child variable”

Terms and definitions Control: used to show that the result of an experiment is really due to the variable being tested Theory: a logical explanation of events that occur in nature (can change when given new information) Law: a theory that has been repeatedly proven true Model: represents an idea, event, or object and helps people to better understand it

An experiment was designed to investigate the effect of caffeine on the heartbeat of water fleas. Two populations were cultured, and both had the same water mineral content, were supplied with identical amounts of bacteria as food, received the same amount of light, and had their temperature maintained at 20ºC. Every two hours, fleas from both populations were selected and their heartbeats were monitored. The fleas of population one had caffeine administered five minutes before their heartbeat was checked. The fleas of population two were given nothing. Identify: 1. Population Two A. Independent Variable 2. The heartbeat? B. Dependent Variable 3. The Caffeine C. Control

Traits of a GOOD hypothesis A good hypothesis states both the independent and dependent variables and also what is happening to each variable Basic Format: If ………………Then ………………, Because (of a connecting reason)

Writing a hypothesis Sample: If the number of hours that a student watches TV increases, then the scores on the student’s science tests decrease, because watching TV takes up time that a student could be using to study.

Scientific method in practice… Question: Does a regular Coke weigh the same as diet Coke? Hypothesis: Tell which you think it is. Experiment: How could we test it? Data: What do you observe happening during your test? Conclusion: Were you right? VS.