Example+Questions+and+Hypotheses

Questions, hypotheses and variables are all connected in science. These are the key parts of any scientific investigation. Understanding how these three ideas work together will make your project go smoother and help you to get a reliable answer to your question.
 * Questions, Hypotheses and Variables **

Below are three examples that should help you to see how these ideas work together. But first let’s define the important types of variables.

Manipulated or Independent Variables are things that the research changes in some way to look for an effect. When you compare two different things, the things are the manipulated or Independent variable. Manipulated means altered or changed, while Independent means one its own. These two terms can be used interchangeably.
 * Manipulated or Independent Variable **

The Responding or Dependent Variable is usually the one a researcher uses to compare things. If you are interested in the difference between two plants you might measure height, weight, leaf number, root mass, color, leaf shape, leaf area, age... All of those measurements would be Responding or Dependent Variables. As above the two terms can be used interchangeably.
 * Responding or Dependent Variable **

A control is a variable that the researcher keeps the same across all of their experimental trials. By keeping the controls the same, the researcher ensures that the controls are not responsible for any of the results.
 * Control **

A scientific question asks about relationships between variables.
 * Scientific Questions and Hypotheses **


 * Example: **


 * Question : Does more bacteria grow on __wooden or plastic cutting boards__ ? **


 * Hypothesis : __Wooden cutting boards__ will have more bacteria . **


 * Variables : **
 * Identify each variable as Manipulated or Responding; Independent or Dependent; or a something to Control. **


 * ** Variables ** || ** Type of variable ** ||
 * __Type of cutting board__ || Manipulated, Independent ||
 * Number of bacteria || Responding, Dependent ||
 * Size of sample || Control ||
 * Age of cutting board || Control ||
 * Cleaning the cutting board || Control ||


 * Graph of Hypothesis: **


 * Example # 2 **
 * Question : Does the __amount of air in a ball__ affect how high it will bounce ? **


 * Hypothesis : Balls with __more air__ will bounce higher than balls with __less air__ . **


 * Variables : **
 * Identify each variable as Manipulated or Responding; Independent or Dependent; or a something to Control. **


 * Variables || Type of variable ||
 * __Amount of air__ || Manipulated, Independent ||
 * Height of bounce || Responding, Dependent ||
 * Type of ball || Control ||
 * Height of drop || Control ||
 * Floor surface || Control ||


 * Graph of Hypothesis: **


 * Example: One manipulated variable and change over time **


 * Question: Do radish plants grow more quickly with __added nitrogen__ ? **


 * Hypothesis: Plants with __added nitrogen__ will grow more quickly . **


 * Variables : **
 * Identify each variable as Manipulated or Responding; Independent or Dependent; or a something to Control. **


 * Variables || Type of variable ||
 * __Added Nitrogen__ || Manipulated, Independent ||
 * Plant growth || Responding, Dependent ||
 * Time (“quickly”) || Independent ||
 * Number of plants || Control ||
 * Type of plants || Control ||
 * Amount of water and light || Control ||
 * Growing environment || Control ||


 * Graph of Hypothesis: **


 * Example : More complicated with two dependent variables **
 * Question : How is __snowmaking snow__ different from __natural snow__ ? **


 * Hypothesis : __Snowmaking snow__ will be more dense and have less shape . **


 * Variables : **
 * Identify each variable as Manipulated or Responding; Independent or Dependent; or a something to Control. **


 * Variables || Type of variable ||
 * __Type of snow__ || Manipulated, Independent ||
 * Density of snow sample || Responding, Dependent ||
 * __Snowflake shape__ || Manipulated, Independent ||
 * Number of flakes with rounded or pointy shape || Responding, Dependent ||
 * Size of sample || Control ||
 * Storage and preparation of sample || Control ||
 * Cleaning the cutting board || Control ||