Variables – Approaching – 01

Think of how you might learn more about a car’s speed. You might ask the question, “Which variables have the greatest effect on a car’s speed in a quarter mile run?” There are many factors that could affect the car’s speed. Those factors are called variables.

Most experiments contain many possible variables. The hard part for most Science students usually comes in deciding which one is which.

The easiest method to identify variables is by starting at the end. Ask yourself, “What is the outcome?” The outcome is dependent on the changes made to the other variables. Think back to the question about the car’s speed. The outcome, or dependent variable, is the speed. You will measure this speed in some units, such as kilometers per hour.

Other variables included in this question are the independent variables. There are many potential independent variables we could change. These variables might include the addition of weight, type of fuel, or type of tires. These might cause changes to the outcome. For example, adding weight to the car might affect the speed. Speed would be the dependent variable. This changes the outcome of the experiment. Another example would be changing the tires on the car. This might also affect the car’s speed.

Can you think of another independent variable that might cause the car’s speed to change? How might this change the outcome of the experiment?