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