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