Introduction
A scientific study involves the systematic and organized study of a relationship between variables, generally two.
For example, a physicist wants to learn the relationship between the depth of water from the surface and liquid pressure; a biologist wants to find out the relationship between calorie intake and sleepiness in human beings; and a chemist wants to investigate the relationship between the surface area of reactants and the rate of a chemical reaction.
Evidently, we study the cause-and-effect relationship between two variables in real life. In the above examples, the depth of water, calorie intake, and the surface area of reactants are the causes; whereas liquid pressure, sleepiness in human beings, and the rate of a chemical reaction are their respective effects.
However, each scientific study comes with several constants too.
Types of Variables of Scientific Research
a) Independent variable
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