Independent and Dependent Variables: Easy to Understand Examples

Independent and Dependent Variables ExamplesScience experiments and studies may be performed on just about any subject matter, from plants to chemical reactions to pharmaceutical trials to humans and animals. While test subjects and theories constantly change, all science experiments must be executed in a similar manner, with control measures, independent variables and dependent variables.

Scientific variables are a little difficult to grasp at first. Sometimes it takes students months to truly understand the purpose and function of variables in science. Read scientific publications, magazines, blogs, and text books and take chemistry courses to gain a better understanding of the requirements and proper procedures of performing scientific experiments.

Why do Science Experiments?

Scientists begin to study a certain topic because it’s interesting to them and they think they can confirm or disprove theories established by others or themselves. A scientist’s job is to learn more about the universe we live in. They want to discover how the world works, why things happen and how to manipulate the environment to best serve mankind. Without scientific experimentation, humans would still live in caves.

Every day advances in science elevate our quality of life, comfort, health and sense of well-being. Medical miracles born of science save and change lives daily. Science teaches us about all types of human health, including physical, psychological and spiritual. Through careful and fair exploration and analysis, science professionals are able to keep making progress and changing lives.

The study of biology is vital to advances in medicine. Learn more about life sciences and the world we live in with an online biology course.

Scientific Variables Made Simple

Imagine for a moment that two plants are sitting on a shelf in identical pots with identical potting soil, light, fertilizer and water. The two plants are as close to the same as possible. A study needs to be performed on the effects of a new organic fertilizer on plant growth. For this experiment, both plants are needed.

The plant on the right will be the independent variable and the one on the left will be the dependent variable. The plants will be treated and cared for in an identical manner, with exception to the fertilizer added to the pot on the right. As the independent variable, the pot on the right will take the brunt of the experimentation.

Control Measures

These two plants are given the same environment for growth, except that the independent variable has ONE condition that is different. Scientists are able to theorize the true effects of the new fertilizer because the conditions were the same for both plants. The only factor that would make a difference is the variant, e.g. the organic fertilizer.

Dependent variables are basically a benchmark with which to launch the experiment or study. It’s a fresh slate, with no pollutants affecting its existence. Independent variables are modeled after the dependent variable, but just give one little tweak.

The results of the scientific experiments, studies and trials may or may not be favorable to the organic fertilizer producer, but that doesn’t matter to scientists. A scientist must always be a professional with a dedication to finding the truth about products, actions and more. Dependent variables may not be manipulated without destroying the integrity of the study.

Learn more about the ethics of business professionals with an ethics workshop found online or at local community colleges. Lessons learned in this course apply to all aspects of life, and this is a wonderful course for instilling honesty and fairness into business professionals.

Examples of Scientific Variables


Independent Variable

Dependent VariableControlled Variable
Ice cubes made from boiling water are clearer than ice cubes made from room temperature tap water.Water Temperature – BoilingWater Temperature – TepidIce cube trays

Amount of water used for each cube

Freezer conditions

Ice cubes made from boiling water contain fewer living organisms than room temperature tap water.Water Temperature – BoilingWater Temperature – TepidIce cube trays

Amount of water used for each cube

Freezer conditions

Water source and collection methods

Water freezes faster than Coca ColaWaterCoca ColaFreezer environment and temperature

Container size, shape, etc.

Plants grow more when exposed to classical musicExposure to classical musicNormal exposure to noises with no musicGrowing environments




Salt makes ice colderIce made from fresh water with salt addedIce made from fresh waterWater composition

Freezer conditions

Girls blink more than boysGirl’s eyesBoy’s eyesHydration levels of the eye

Eye health


Corn plants grow bigger in full sunlightFull sunlightPartial sunlightWater




Exercise improves healthExerciseNo exerciseTest subjects with similar health issues
Blood pressure medicine lowers blood pressureHigh BP patient uses blood pressure medicationHigh BP patient uses no blood pressure medicationDiet and Exercise

Weight, Height, Age, Sex, income, family situation


Stress levels

Viewing beauty regulates vital signsTest subject viewing beautiful imagesTest subject viewing average imagesTesting environment

Healthy test subjects of the same sex, age, etc.

Stress levels

Vital Signs

Meditation helps ease stressMeditationNo meditationStress levels


Support insoles help eliminate back and hip painShoe insolesNo shoe insolesSimilar health problems, activity levels and pain levels

Scientific studies can be fun and lighthearted or serious and urgent. Biology or chemistry labs are a great place to find fun experiments to perform. Most schools make it simpler for students to create identical controlled environments for test subjects than outside of schools. With the proper environment, equipment and knowledge, learning about the world is actually enjoyable and an activity many choose to do voluntarily. Not only is it possible to have fun experimenting with science, it can save lives, improve quality of life for the masses and makes us happier.

If experimentation at home sounds like an interesting way to pass the time or getting into the serious side of science sounds fascinating, there is a series of four chemistry courses available through Udemy to help teach the basics of performing a study, trial or simple experiment right from home. Sign up for Chemistry 101 and start learning today.