allan_sanders_2006-science-strip2-724519.jpg "Experiment")
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In order to accurately evaluate a hypothesis, some sort of study or experiment must be designed to observe and analyze any repeatable pattern or relationship. The purpose of the study is to generate reliable data that can be used to support or reject a hypothesis.
The study design is a plan that outlines what the experiment or study will entail, and how the results from the study will be used to evaluate the hypothesis.
Sometimes a study simply involves analyzing existing data to observe correlations between two variables. Other times, a study will involve an actual experiment that tests one or more variables to gather data.
A study must be carefully designed to be objective and account for all variables present. This is very important to consider, because although you are testing a hypothesis, your primary goal as a scientist is to present results that can be trusted, not to prove that your hypothesis was correct.
In an experiment, there can be many different factors that impact the outcome of an experiment. The variables that are being tested as a potential “cause” of something are called independent variables. The measured “effect” or change that is observed as a result of the variation of the independent variable is called the dependent variable.
Throughout the rest of this article, the word “variable” will used to mean independent variables unless otherwise stated.
Sometimes all variables are known and can all be controlled, but sometimes the outcome of an experiment will indicate that additional variables exist that need to be accounted for in some way.
When all independent variables are known and can be controlled, one variable is chosen to be an experimental variable. This means that this variable will be intentionally changed to observe any change in the dependent variable, and all other variables will be standardized, or controlled.
In many experiments, a control experiment is also performed. A control experiment contains an experimental variable that is known to cause no change in the dependent variable. A control is useful for comparing the amount of change that each independent variable causes in the dependent variable.
Assignment:
Watch the video.
Answer the following questions.
- What do you think is the purpose of this experiment?
- What is the purpose of the stunt man doing practice jumps?
- What are the safety concerns presented in this video?
- Specifically, what components of this prototype are they testing?
Video: Personal Airbag
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