140 likes | 316 Vues
Identifying Variables. Please take notes on the following slides. Hypothesis Review…. If Stephen thinks that energy drinks will help him have more energy all day long… Can you write a hypothesis for this scenario? If…Then…Because
E N D
Identifying Variables Please take notes on the following slides.
Hypothesis Review… • If Stephen thinks that energy drinks will help him have more energy all day long… • Can you write a hypothesis for this scenario? If…Then…Because Scenario Outcome Reason why
Independent Variable • What the scientist changes…what is being tested • If Stephen drinks energy drinks instead of water • Then he will have more energy • Because energy drinks contain sugar and caffeine. • What is being tested or changed?
Independent Variable • Stephen is testing…. ENERGY DRINKS
Dependent Variable • What the independent variable changes…what is measured • If Stephen drinks energy drinks instead of water • Then he will have more energy • Because energy drinks contain sugar and caffeine. • What is the outcome?
Dependent Variable • What is being measured? HOW MUCH ENERGY STEPHEN HAS!
Control Group or Constant • What stays the same… • For his experiment, Stephen wants to test different energy drinks. For one week, he drinks an 8 oz. can of a different energy drink each morning. • What stays the same despite the change in energy drink?
Control Group or Constant • What stays the same? STEPHEN ALWAYS DRINKS 8 OZ. & HE ALWAYS DRINKS IT IN THE MORNING.
Let’s Try Some… • Martin believes that lemon juice will keep apple slices fresh longer. He puts 4 apple slices in a bag with lemon juice and 4 apple slices in a bag with no juice. He observes each bag until the apples turn brown. • What is the independent variable? • What is the dependent variable? • What is the constant (or control)?
How did you do? • Independent Variable – lemon juice • Dependent Variable – time it takes to turn brown • Constant (or Control) – 4 apple slices in a sealed bag
Let’s Try Another One… • Juan wants to see if new shoes will affect how high he jumps. He measures how high he jumps in his old shoes and then measures his jump with his new shoes. • What is the independent variable? • What is the dependent variable? • What is the constant (or control)?
How did you do? • Independent Variable – shoe type • Dependent Variable – height of his jump • Constant (or Control) – wears shoes & where he jumps
One More… • Ceiona wants to see if diet soft drinks will freeze faster than regular soft drinks. She pours 8 oz. of each drink into a glass and places them in the freezer. She checks the drinks every hour and then records her findings. • What is the independent variable? • What is the dependent variable? • What is the constant (or control)?
How did you do? • Independent Variable – type of drink (diet or regular) • Dependent Variable – time till freezes • Constant (or Control) – 8 oz. of soft drink, glass cups, same freezer & freezer temperature