Recap the Scientific Method Recap Formulating a Hypothesis Recap Control Groups vs. Experimental Manipulated Variables Responding Variables Recap the Scientific Method Recap Formulating a Hypothesis Recap Control Groups vs. Experimental Manipulated Variables Responding Variables Manipulated vs. Responding Variables

Recapping… What are five steps to the scientific method: 1) Identify the problem & formulate a hypothesis 2) Create a procedure to test the hypothesis 3) Make observations based on the experimental procedure 4) Analyze the data 5) Draw Conclusions

Recapping… The Hypothesis is a very carefully designed and __________ statement used to isolate a __________ How many variables can the hypothesis test at once? The hypothesis should use _____ / ________ statements

Recapping… “If” & “than” statements The “if” part of the statement should explain what you are doing. The “than” part of the statement should explain what you’re measuring/expecting to find.

Recapping…. What is the whole purpose behind having a CONTROL GROUP and an EXPERIMENTAL GROUP? By having a control group we have a base line of comparison to see what the effects of the manipulated variable were?

3 Types of Variables Every experiment will have three types of variables. They are: 1.Controlled Variables 2.Manipulated variable 3.Responding Variable

Controlled Variables Controlled Variables are… All of the different things that could vary and affect the outcome of an experiment that are deliberately kept the same. Going back to the lawn example… What are some CONTROLLED variables that we would need to make sure are kept the same when testing the fertilizer out on the lawn?

Manipulated Variable The Manipulated Variable is… The only thing that is changed or varied between the control group or the experimental group. THERE CAN ONLY BE ONE MANIPULATED VARIABLE PER EXPERIMENT… why?

Manipulated Variable Going back to the lawn example… What was the manipulated variable in the experiment where we wanted to see what would happen if we added more fertilizer to our lawn? Why cant we change the amount of water we give the control and experimental groups as well?

Responding Variable The Responding Variable is… The difference in outcomes between the control group and experimental group Its how the experimental group RESPONDED to the manipulated variable (the part that we measure) What would we expect the responding variable to be in our lawn example where we added more fertilizer?

Manipulated vs. Responding Recap the difference The Manipulated Variable is… The one and only factor in an experiment which is changed on the experimental group. The Responding Variable is… The different reaction we get from the experimental group over the control group

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What are some examples of possible manipulated variables in these pictures and what would you expect the responding variable to be?

Start to Finish… As a class, we are going to… Identify the problem Create a hypothesis Differentiate between the control and experimental groups List the controlled variables we need to account for List the manipulated variable Suggest a few possible responding Variables

Start to Finish… NASCAR wants to find the effects of using harder rubber in the new tires for the race cars and what that does to lap times! Identify the problem Create a hypothesis What are the control and experimental groups List the controlled variables we need to account for List the manipulated variable Suggest a few possible responding Variables

Assignment for next class Once again, You will be given a short worksheet but you must work on this one alone for the first bit Hot tip… Check the last question 1 st