1. Planning a Speed Investigation You will choose the independent variable. GOAL: find a way to increase the velocity of the car once it crosses the photogate at bottom of ramp.

2. How to Set up Ramp

3. Pass out sheet Variable and Controls: Independent variable – the variable you will change (3 levels) Dependent variable – what you will measure (result depends on what you changed) Experimental control – what will you compare your results to? Controlled variables – at least three variables that you will keep the same in all trials

4. Write down your independent variable choices: Adding mass - mass balls – 1,2,3 Placement of mass balls – front, middle, rear hole Rubber bands – distance stretched - # of rubber bands – 1,2,3 Height of ramp Placement of photogate – high, medium, low

5. Controlled Variables (EXAMPLES)… you need to choose ones the relate to YOUR lab experiment Placement of photogates Same kind of car with tires Location tested Length of ramp Use same equipment set-up each trial Same release method (don’t push the car) Use a windless location Photogate distance and exact placement on ramp Person who releases car and same method

6. Sections of your lab write up Title: The effect of ____________________ on the speed of cars Question: Does ________________________influence how fast a car go down a ramp? Hypothesis: Write a Hypothesis (If, then, because) Materials : Brief description of the apparatus and your independent variable. Procedures : Data: Data table and bar graph (independent variable vs. avg. speed) Conclusion: Use your data to write a conclusion. Control data is NOT included in your analysis

7. Procedure: 1. Include an annotated (labeled) drawing of your set up. 2. Create a numbered description of steps: a. Must explain experimental group, with dependent variable and 3 levels, and control group. b. Must detail what to measure (dependent variable) and how to record c. Must tell you how many trials (at least 3) and to calculate average d. Must indicate 3 controlled variables e. Must tell you to calculate and record speed

8. ConditionTrial 1 Time Trial 2 Time Trial 3 Time Average Time Experimental Control Condition Condition 1 Condition 2 Condition 3