Experimental Design--ID IV, DV, Constants and Controls
For each experimental question, identify the independent variable (IV), dependent variable (DV), constants and the control.
For Each, Ask Yourself:
What am I changing on purpose so that I can answer my question? -- this is your Independent Variable.
What is being measured? What data (numbers) are being collected? --this is your Dependent Variable.
What is staying the same in all of the exeriments? -- these are your Constants.
What is your zero IV level? What is your normal group that does not recieve any testing.---This is your Control
Does the brand of allergy medication affect the number of times a person sneezes?
No allergy medicine
The person taking the medicine
The number of sneezes
The amount of allery medicine
The time of day medicine is taken
The brand of medicine
Independant Variable
Dependent Variable
Constants (3)
Control
Does the amount of soil a plant is placed in affect how tall it grows?
Height of plant (in cm)
No soil
type of plant
amount of water
Amount of soil
amount of sunlight
Independant Variable
Dependent Variable
Constants (3)
Control
Which type of sunscreen prevents burns for the longest amount of time?
Time of day
Time to burn (minutes)
amount of sunscreen used
skin tone of persons being tested
No sunscreen
Brand of sunscreen
Independant Variable
Dependent Variable
Constants (3)
Control
What paper towel brand absorbs the most water?
Temperature of water
None (need a paper towel to absorb any water)
Amount of water absorbed (mL)
Surface water is spilled on
Brand of paper towel.
Size of paper towel
Independant Variable
Dependent Variable
Constants (3)
Control
Sam wants to figure out which pan cooks eggs the fastest: bronze, copper or steel.
Temperature stove burner is set on.
Minutes until egg is cooked
None (can't cook eggs without a pan)
Size of eggs
Size of pans
Material pan is made out of.
Independant Variable
Dependent Variable
Constants (3)
Control
Ashton wants to see which fast food restaurant has french fries that will take the longest to grow mold.
Handle french fries with gloved hands
Fries from different restraurants
Number of french fries
French fries are on the same table
None (can't test without french fries)
Time to grow mold (days)
Independant Variable
Dependent Variable
Constants (3)
Control
Which brand of dish soap makes the most amount of suds?
Brand of dish soap.
Amount of dish soap
Amount of water
Volume of suds (mL)
None (need suds to make bubbles)
Time water and soap is stirred
Independant Variable
Dependent Variable
Constants (3)
Control
What type of physical activity gives you the highest heart rate?
Time spent on activity
Type of physical activity
Person doing the activity
Outside temperature
Sitting (no activity)
Heart rate (beats per minute)
Independant Variable
Dependent Variable
Constants (3)
Control
What type of detergent gets out grass stains the best?
Type of original stain
Area of stain removed (cm^2)
Size of original stain
Brand of detergent
Same wash cycle
washed in water without detergent
Independant Variable
Dependent Variable
Constants (3)
Control