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 person taking the medicine
The time of day medicine is taken
No allergy medicine
The brand of medicine
The number of sneezes
The amount of allery 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
No soil
Height of plant (in cm)
type of plant
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?
skin tone of persons being tested
Time of day
No sunscreen
Brand of sunscreen
amount of sunscreen used
Time to burn (minutes)
Independant Variable
Dependent Variable
Constants (3)
Control
What paper towel brand absorbs the most water?
Temperature of water
Surface water is spilled on
Amount of water absorbed (mL)
Size of paper towel
None (need a paper towel to absorb any water)
Brand 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.
None (can't cook eggs without a pan)
Temperature stove burner is set on.
Size of eggs
Size of pans
Material pan is made out of.
Minutes until egg is cooked
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)
Fries from different restraurants
French fries are on the same table
Number of french fries
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?
Brand of dish soap.
Amount of water
Volume of suds (mL)
Time water and soap is stirred
Amount of dish soap
None (need suds to make bubbles)
Independant Variable
Dependent Variable
Constants (3)
Control
What type of physical activity gives you the highest heart rate?
Time spent on activity
Outside temperature
Person doing the activity
Heart rate (beats per minute)
Type of physical activity
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
Size of original stain
Same wash cycle
Area of stain removed (cm^2)
Type of original stain
Brand of detergent
Independant Variable
Dependent Variable
Constants (3)
Control