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What is an Independent variable?
Question Date: 2017-10-31
Answer 1:

An independent variable is something that scientists change in an experiment. A dependent variable is something that changes BECAUSE of the independent variable. In other words, the dependent variable DEPENDS on the independent variable. The dependent variable is usually what scientists measure in an experiment.

For example, let’s say you wanted to do an experiment to see what things make plants grow taller. You predict that the amount of water a plant receives will affect its height. So you design an experiment where you plant two seeds: one seed will be watered every single day, and the other seed will be watered only once a week. You measure the height of the plant every week for a few months, and at the end of the experiment you will see which plant is taller. In this case, the amount of water is the independent variable because that is what you're changing in the experiment: one seed gets a lot of water and the other seed only gets a little water. The dependent variable is the height of the plant, because you predict that the height is going to change DEPENDING on how much water the plant receives.


Answer 2:

An "Independent variable" can mean a lot of different things. In math, it usually refers to a variable that does not depend on another variable. The word "independent" generally always means just that - think about the July 4th holiday here in America - Its called "Independence Day", where we decided we did not want to depend on Great Britain for help anymore.

So lets say you have the equation in math:
y = x + 2
in this case, y is dependent on x for its value, and depending on what x is, will always be 2 more than that. So in this case, x is the independent variable, because it doesn't depend on y to decide what it is.

Hope that helps!

Answer 3:

Thanks for the great question.

One way that scientists learn things about the world is by doing experiments. Scientists like experiments because it allows them to carefully control and measure important things they want to study.

In an experiment, the independent variable is what the scientist has control over, it is the thing that the scientist gets to decide. The dependent variable is different, it is what the scientist looks at or measures, but does not get to decide. Typically, the scientist wants the independent variable to change the dependent variable.

Let’s think of an example.
Imagine you have made a new drug that you think will make people’s memory better. To show that the drug works, you have to run an experiment. The independent variable would be whether you give the drug to someone or not, as this is under your control. The dependent variable could be a test of how well they remember things. If those who took the drug remember things better than those who did not, the drug works!

Thanks again for your question!


Answer 4:

Variables are things we measure. When conducting an experiment or study, we are usually interested in the relationships among these variables. These relationships determine if a variable is independent or dependent. An independent variable DOES NOT change because of the other variables in the study. On the other hand, a dependent variable DOES change because of other variables.

For example, we are interested in how your height changes with time. In this study, there are 2 variables, height and time. You get taller as time passes. However, time does not pass because you get taller. Time will pass even when you stop growing. In this study, time is the independent variable and height is the dependent variable.

Answer 5:

When you make a graph of something, the independent variable is on the X-axis, the horizontal line, and the dependent variable is on the Y-axis, the vertical line. If one axis is time, it's always the X-axis, the independent variable. For example, you might measure how tall your plant is every day or every week.

I've attached a graph - on the X-axis it has how many hours students studied for an exam. On the Y-axis, it has their score on the exam. Do you think the students got better scores when they studied longer? I don't think the graph shows real data - I think it's just an example of independent and dependent variables.

But your question is a hard question, and there are many ways to answer it. Wikipedia has a description of dependent and independent variables: read here


Answer 6:

An independent variable is a variable that is not affected by another variable, but which does (or may) have an effect on another variable.

For example, suppose you want to measure the effect of the temperature of a star on the temperature of its planets. The star will have the temperature that it does because of the star's mass and stage of it's life - it has nothing to do with the planets that orbit the star, if there even are any. The planets will be much hotter if they orbit a hotter star, though, because hotter stars put out more light. In this relationship, the temperature of the star is an independent variable while the temperature of the planet is a dependent variable.


Answer 7:

A variable is a way of representing a quantity that changes. For instance, variables you see every day may include the amount of water you drink, or the number of hours you spend reading books.

An independent variable is a variable whose change does not depend on the change of other quantities. In an experiment, independent variables are the quantities you change in order to change other quantities. For instance, if you were doing an experiment in which you want to find out how the number of hours of sunlight exposure affects plant growth, you might have two variables: number of hours of sunlight given to the plant per day, and the height of the plant. In this case, the number of hours of sunlight is the independent variable and the height of the plant is the dependent variable, because the change in the height depends on the hours of sunlight, not the other way around.

Answer 8:

At the heart of a scientific experiment, you are testing how something responds to some form of your input. When running an experiment, you repeat it many times, changing one part every time and observing what happens. This thing you're changing is called the independent variable (it's called a vary-able because you can vary it!).

Everything you then measure is called a dependent variable, because these depend on the in(in meaning not)dependent variable. This is vague so let's consider an example:

Imagine an experiment looking at flower growth. Plant a bunch of identical seeds in separate pots and let them grow next to each other with only one difference among them.

This difference could be how much you water them, then the amount of water each plant receives is the dependent variable.

There can then be many dependent variables for an independent variable, but examples here could be how fast or tall the flower grows or what colors its petals are.


Answer 9:

When working with equations it is really important to understand the difference between independent and dependent variables.

An independent variable is a variable that does not depend on anything else for it to occur, while the dependent variable changes based on the value of the independent variable.

This may sound a little confusing, so let’s look at an example. Let’s say that we were measuring how tall a plant grew over time. In this scenario, time is an independent variable because it does not depend on anything else for it to occur, it just happens on its own. This is different from the dependent variable: the plant’s height. The plant’s height changes as time goes on. The change in height is directly controlled by time. The dependent variable is always controlled by the independent variable. I hope this answers your question!



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