1. Experimental Design
And Variables

2. How does mass affect the acceleration of a car?
Amount of stuff
Acceleration?
How long does it take to go from 0-60 mph?

3. How does mass affect the acceleration of a car?
If a car has more mass,
it will take ____ (more or less) time
to get from 0-60 mph.

4. Testing our Hypothesis.
How many variables will change?
Only ONE
What will be the only difference?
The mass
What is the name for the variable that will be changed by us?

5. Controlling other variables
What should we make sure stays the same every time?
Why is it important to keep these things the same?

6. Measuring the acceleration.
We change the mass and then see what happens to acceleration.
What is the name of this kind of variable that we measure?
Dependent variable.
How will we measure the acceleration?

7. Saturn
0-60 mph in 16.6 seconds
2,000 pounds
Subaru wrx impreza
0-60 mph in 5.2 seconds
3,000 pounds

8. Tundra
0-60 mph in 8 seconds

9. Experimental Design What is the independent variable? mass
What is the dependent variable?
acceleration
What are the controlled variables?
Size of engine, road conditions, ….
What other factors might we test?