Dependent Variables
Define Dependent Variables
Variables that are changed by the independent variable changing
Define Constants
Constants are variables that are kept the same in the experiment
Define a control
A Control is the original value of the dependent variable without any changes to the independent variable
Define independent variables
Variables that are changed on purpose in an experiment
I am running an experiment to discover which dish soap is the best for cleaning dirty pans. I test three different soap brands. What is the dependent variable?
The cleanliness of the pans
How many constants can you have in an experiment?
As many as you need/can have
If I want to do an experiment to find the effect of studying on my test scores. What should my control be?
Taking a test without studying at all.
I am running an experiment to discover which dish soap is the best for cleaning dirty pans. I test three different soap brands. What is the independent variable?
Type of dish soap I use
If I want to figure out whether adding more merits to a class increases participation, what is my dependent variable in the experiment?
Amount of student participation
I am running an experiment to discover which dish soap is the best for cleaning dirty pans. I test three different soap brands. What would some constants be?
Type of mess in the pan, material of pan, type of sponge/cleaning tool
If I want to do an experiment to find the effect of different dish soaps on how clean my pans can get, what should the control be?
Washing the pan with only water
I am running an experiment to find the effect of breakfast foods on my class performance. I eat cereal, oatmeal, eggs and no breakfast. What is the independent variable?
The different types of food I eat.
I want to see how fast ice freezes in a freezer at different temperatures. I put ice in a freezer at 30 degrees, 10 degrees, and -10 degrees. What is the dependent variable?
Amount of time it takes for water to freeze
I am running an experiment to find the effect of breakfast foods on my class performance. I eat cereal, oatmeal, eggs and no breakfast. What are some things that you would need to keep constant?
Amount of time studying, amount of sleep,
If I want to figure out how my new shoes affect my jumping height, what should my control be?
The height that I can jump with no shoes on
I want to see how fast ice freezes in a freezer at different temperatures. I put ice in a freezer at 30 degrees, 10 degrees, and -10 degrees. What is the independent variable?
Temperature of the freezer the ice is in
I am testing the effect of amount of sleep on my quiz scores. I sleep for 6, 8 and 10 hours and record my quiz scores from the next day. What is the dependent variable?
My quiz scores
Why are constants important?
So that we can be sure of the effect of the independent variable on the experiment. Without constants, other things may change our experiment
Why are controls important?
To see how much the independent variable changes from its original value
I am testing the effect of amount of sleep on my quiz scores. I sleep for 6, 8 and 10 hours and record my quiz scores from the next day. What is the independent variable?
Amount of time spent sleeping