Understanding Hypotheses and Variables

What is an independent variable in an experiment?

• The variable that is measured or observed.

• The variable that is manipulated or changed by the researcher.

• The variable that remains constant throughout the experiment.

• The variable that depends on other variables.

What does a dependent variable represent in an experiment?

• The outcome that the researcher is trying to measure.

• The factor that is kept constant throughout the experiment.

• The factor that the researcher changes.

• The hypothesis being tested.

What is a controlled variable?

• A variable that changes in response to the independent variable.

• A variable that is manipulated by the experimenter.

• A variable that is kept the same throughout the experiment.

• The result of an experiment.

In an experiment to test the effect of sunlight on plant growth, what is the independent variable?

• The type of plant.

• The amount of water given to the plants.

• The amount of sunlight the plants receive.

• The height of the plants.

In the same experiment, what is the dependent variable?

• The amount of sunlight the plants receive.

• The height of the plants.

• The type of soil used.

• The time of year the experiment is conducted.

Which of the following is an example of a controlled variable in a plant growth experiment?

• The color of the plants.

• The amount of water each plant receives.

• The type of plant being tested.

• The height of the plants at the start of the experiment.

If you are conducting an experiment to see if studying more hours leads to better test scores, what is the independent variable?

• The subjects being studied.

• The test scores.

• The number of hours spent studying.

• The type of test.

In the same study, what would be the dependent variable?

• The number of hours spent studying.

• The test scores.

• The type of test.

• The subjects' previous test scores.

Which of the following best describes why controlled variables are important in an experiment?

• They ensure that the experiment can be repeated.

• They are the variables that are being tested.

• They prevent other factors from affecting the outcome of the experiment.

• They are the result of the experiment.

In an experiment to determine if fertilizer increases plant growth, the type of fertilizer used is what kind of variable?

• Independent variable.

• Dependent variable.

• Controlled variable.

• None of the above.