1. Independent Variable vs Dependent Variable
Aim: How to identify the independent variable and dependent variable in an experiment?

2. Variables & Controls
A variable is anything that changes in a scientific experiment.
The control is what you use to compare the results to in the end of the experiment.

3. There are 2 types of variables:
Independent Variable
Dependent Variable

4. Identifying the Independent Variable
The Independent Variable goes after the “If”
I.V.
If the amount of fertilizer is increased, then the height of the plant will increase.

5. Identifying the Dependent Variable
The Dependent Variable goes after the “Then”
If the amount of fertilizer is increased,
then the height of the plant will increase.
D.V.

6. Now You Try: (Use the previous 2 slides to guide if you’re stuck)
Example # 1
If you spend more time studying, then your grade will improve.
Independent Variable = _______________
Dependent Variable = ________________

7. Now You Try:
If you spend more time studying, then your grade will improve.
Independent Variable = amount of time spent studying
Dependent Variable = grade

8. Now You Try
Example # 2
If the temperature of the room is increased, then the bacteria will grow faster.
Independent Variable = _______________
Dependent Variable = ________________

9. Now You Try
Example # 3
If plants get sunlight, then they will grow faster.
Independent Variable = _______________
Dependent Variable = ________________

10. Now You Try
Example # 4
If you wear Nike sneakers, then you will run faster.
Independent Variable = _______________
Dependent Variable = ________________

11. Now You Try
Example # 5
If you take Tylenol, then your headache will be reduced.
Independent Variable = _______________
Dependent Variable = ________________

12. Now You Try
Example # 6
If you exercise, then your heart rate will increase.
Independent Variable = _______________
Dependent Variable = ________________

13. Now You Try
Example # 7
If the salt concentration is increased, then more brine shrimp will hatch.
Independent Variable = _______________
Dependent Variable = ________________

14. Lesson Summary Questions How are variables different than controls?
How many different variables are there?
How can you tell the independent variable from the dependent variable in a hypothesis?

15. Any Questions????