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