Controlled variables
Controlled variables, also known as constant variables, are the factors in a scientific experiment that are intentionally kept consistent or unchanged throughout the experiment. They are crucial to ensure that any observed changes or effects are solely due to the manipulated variable (independent variable) and not influenced by any other factors.
Controlled variables are important in experiments because they help establish a baseline and reduce the possibility of confounding or extraneous variables affecting the results. By keeping these variables constant, researchers can isolate the effects of the manipulated variable and accurately measure its impact.
Some common examples of controlled variables include:
1. Temperature: Keeping the temperature constant ensures that any observed effects are not a result of temperature variations.
2. Time: Controlling the time frame of an experiment helps in comparing results accurately, especially when monitoring changes over a specific period.
3. pH: Maintaining a consistent pH level ensures that acidity or alkalinity does not influence the outcome.
4. Light intensity: Controlling the amount of light exposure prevents any variations in growth or reaction rate due to varying light conditions.
5. Concentration of substances: Maintaining the same concentration of chemicals or substances being used in the experiment helps to isolate the effects of the manipulated variable.
6. Pressure: Keeping pressure constant eliminates any potential effects on the outcomes.
By controlling these variables, researchers can focus on the effects of the independent variable and draw more reliable conclusions from their experiments.