Presentation on theme: "Objectives: 1. Recognize that a scientific study always begins with qualitative/quantitative observations. 2. Understand that a hypothesis represents a."— Presentation transcript:
Objectives: 1. Recognize that a scientific study always begins with qualitative/quantitative observations. 2. Understand that a hypothesis represents a tentative explanation for the initial observation. 3. Realize that an experiment is necessary to test a hypothesis; understand the distinction between dependent and independent variables, as well as the importance of a control in an experiment. 4. Recognize the importance of data analysis in reaching a conclusion that can either support or disprove the hypothesis. 5. Distinguish among law, theory and inference. What are the steps of the scientific method?
Scientific Method 1. Define the scientific method. 2. List the steps of the scientific method. 3. What is the difference between an independent and a dependent variable? 4. What is a control group and why should it be included in all experiments? 5. Why is it important to have more than a couple of experimental subjects?
Scientific Method Lucy has made some homemade cough syrup. She believes that people will cough the least if they take 2 teaspoons of the cough syrup every 4 hours. Her data is in the following table. 1. What is the hypothesis? 2. What is the independent variable? 3. What is the dependent variable? 4 Which group is the control group? 5. What should Lucys conclusion be? Group# of Coughs/ hr # Tsp of Syrup A203 B252 C301 D400
Scientific Method 1. What is the hypothesis? 2. What is the dependent variable? 3. What is the independent variable? 4. Which group is the control group? 5. What should Quintens conclusion be? Quinten wanted to know which bug spray is the best at repelling mosquitoes. He decided to test three brands of bug spray repellant that he labeled A, B, and C. Quinten had always used brand A in the past, so he believed that it would repel mosquitoes the best. He decided to measure the number of mosquito bites that people using these brands got. He applied the same amount of bug spray to each person and placed them in rooms containing the same number of mosquitoes. After an hour, he counted how many mosquito bites each person had gotten. GroupBrand of Bug Spray # of mosquito bites 1A4 2B7 3C2 4None15
Scientific Method You notice that your houseplant is dying. You want to figure out how to make it healthy again. Design an experiment to determine what is wrong. 1. State your hypothesis. 2. What is your independent variable? 3. What is your dependent variable? 4. What will be your control group?