What is independent variable and the dependent variable in the experiment bellow?

Question

I place two cups of water outside one with salt and another one without salt, and i want to find out wich one evaporates faster.

Answer 1

Ok, first to define your terms:
Independent Variables (IV) & Dependent Variables (DV)

In an experiment, the independent variable is the variable that is varied or manipulated by the researcher, and the dependent variable is the response that is measured.

An independent variable is the presumed cause, whereas the dependent variable is the presumed effect.


In experiments, the IV is the variable that is controlled and manipulated by the experimenter; whereas the DV is not manipulated, instead the DV is observed or measured for variation as a presumed result of the variation in the IV.

"In nonexperimental research, where there is no experimental manipulation, the IV is the variable that 'logically' has some effect on a DV. For example, in the research on cigarette-smoking and lung cancer, cigarette-smoking, which has already been done by many subjects, is the independent variable." (Kerlinger, 1986, p.32)

So to answer your question, if you place two cups of water outside, one with salt and another without, and you check to see which evaporates faster, than the glass without salt would be a dependent variable. The independent variable would be the glass with salt.

For example, The following is a hypothesis for a study.

1. "There will be a statistically significant difference in graduation rates of at-risk high-school seniors who participate in an intensive study program as opposed to at-risk high-school seniors who do not participate in the intensive study program." (LaFountain & Bartos, 2002, p. 57)

IV: Participation in intensive study program. DV: Graduation rates.

It can be confusing at times... hopefully i got it right! After all, I am a psychology major...

Answer 2

What other factors are you going to control? If you are measuring evaporation rate, then one would conclude evaporation is dependent upon some factor so the rate if evaporation would be your dependent variable. Your independent variable will be the ones you control such as air flow, temperature, humidity, salt etc.

Just tossing some salt in a cup and comparing it to a cup w/out salt isn't much of an experiment.

What did you observe that led you to think that salt affects evaporization rates. How does this experiment actually test that and rule out other factors. How are you going to control all the other variables like those mentioned above.

For example, consider the following all of which would be independent variables that you control while observing and measuring their effects on the rate of evaporization(the dependent variable):

How does temperature affect the rate?
How does humidity affect the rate?
How does the depth of the liquid affect the rate?
How does the material that the cup is made of affect the rate?
How does airflow(wind or a fan blowing across) affect the rate? Of course, you can't control the wind so it wouldn't be a good variable to include in your experiment.
How does light or darkness affect the rate?
Does the type of solute matter? For example, does salt have the same effect as sugar? As epsom salts?

These are all things you could test for that would allow you to gather more useful data and actually arrive at a valid conclusion supported by experimental results.

Answer 3

The different variables are the controlled, independent, and dependent responding variables. The controlled variables are what you keep the same in the experiment. The independent variables are what you change on purpose in order to find the results. The dependent variable is what the results are based on the independent variables.

Answer 4

I assume you will measure evaporation by volume loss of weight change. Either of these variables will be dependent of the the independent variable time.

Answer 5

You control solute concentration and measure the evaporation. . . so, the former is the independent variable and the latter the dependent variable.

Answer 6

independant: water w/ salt.
dependant: which cup evaporates faster.