Variables in Scientific Investigation

Justin wanted to determine the levels of pollution that a fish could withstand. He placed fish in tanks with different pollution levels and timed how long they could live under those conditions. What is his independent variable?

• survival rate of the fish

• levels of pollution

• type of pollution

• type of fish

Gerlie was investigating how fast it took Hayden to react to different sounds. What is the dependent variable of the study?

• reaction time of Hayden

• volume of each sound played

• length of time the sounds are played

• different positions of Hayden while listening

In an experiment, it is one factor being tested

• data

• variable

• control

• hypothesis

What is an independent variable?

• It is the variable that is manipulated by the researcher in an experiment

• it is the variable that relies on another variable

• it is the variable that is represented by the experimental group

• it is the variable that is kept constant in an experiment

What is a dependent variable?

• it is the variable that is manipulated by the reseracher in an experiement

• it is the variable that relies on another variable

• it is the variable that is represented by the control group

• it is the variable that is kept constant in an experiment