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?
The time of day medicine is taken
The brand of medicine
The amount of allery medicine
The person taking the medicine
The number of sneezes
No allergy medicine
Independant Variable
Dependent Variable
Constants (3)
Control
Does the amount of soil a plant is placed in affect how tall it grows?
Amount of soil
amount of water
type of plant
No soil
Height of plant (in cm)
amount of sunlight
Independant Variable
Dependent Variable
Constants (3)
Control
Which type of sunscreen prevents burns for the longest amount of time?
skin tone of persons being tested
Brand of sunscreen
No sunscreen
amount of sunscreen used
Time to burn (minutes)
Time of day
Independant Variable
Dependent Variable
Constants (3)
Control
What paper towel brand absorbs the most water?
Surface water is spilled on
Size of paper towel
None (need a paper towel to absorb any water)
Amount of water absorbed (mL)
Brand of paper towel.
Temperature of water
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.
None (can't cook eggs without a pan)
Size of pans
Material pan is made out of.
Minutes until egg is cooked
Size of eggs
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.
None (can't test without french fries)
Handle french fries with gloved hands
Number of french fries
French fries are on the same table
Fries from different restraurants
Time to grow mold (days)
Independant Variable
Dependent Variable
Constants (3)
Control
Which brand of dish soap makes the most amount of suds?
Amount of water
Brand of dish soap.
Time water and soap is stirred
Volume of suds (mL)
None (need suds to make bubbles)
Amount of dish soap
Independant Variable
Dependent Variable
Constants (3)
Control
What type of physical activity gives you the highest heart rate?
Outside temperature
Time spent on activity
Heart rate (beats per minute)
Sitting (no activity)
Type of physical activity
Person doing the activity
Independant Variable
Dependent Variable
Constants (3)
Control
What type of detergent gets out grass stains the best?
Brand of detergent
washed in water without detergent
Type of original stain
Size of original stain
Area of stain removed (cm^2)
Same wash cycle
Independant Variable
Dependent Variable
Constants (3)
Control