Variables Independent Dependent Controlled Independent Variable The variable
Variables Independent, Dependent & Controlled
Independent Variable ü The variable that is presumed to affect or determine a dependent variable. ü It is the thing that someone actively changes. ü The independent variable is the presumed cause. ü A good experiment has only one independent variable.
Dependent Variable ü This variable is the response that is measured. ü It is the presumed effect. ü It changes as a result of the independent variable.
Controlled Variables ü Quantities that a scientist wants to remain constant. ü They are constant as to not affect the results of the dependent variable. ü Most experiments have more than one controlled variable.
Examples: ü If you open a faucet (the independent variable), the quantity of water flowing (dependent variable) changes in response.
Practice Question Independent Variable (What I change) How much Water faucet water flows opening (closed, through a half open, fully faucet at open) different openings? Dependent Variables (What I observe) Controlled Variables (What I keep the same) Amount of • The faucet water flowing • Water measured in pressure liters per minute
Practice Question Does heating a cup of water allow it to dissolve more sugar? Independent Variable (What I change) Dependent Variables (What I observe) Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Does heating Temperature of a cup of Water water allow it to dissolve more sugar? Dependent Variables (What I observe) Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Does heating Temperature of a cup of Water water allow it to dissolve more sugar? Dependent Variables (What I observe) Amount of sugar dissolved Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Does heating Temperature of a cup of Water water allow it to dissolve more sugar? Dependent Variables (What I observe) Controlled Variables (What I keep the same) Amount of sugar dissolved Amount of Water
Practice Question Does fertilizer make a plant grow bigger? Independent Variable (What I change) Dependent Variables (What I observe) Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Does fertilizer make a plant grow bigger? Fertilizer Dependent Variables (What I observe) Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Dependent Variables (What I observe) Does fertilizer make a plant grow bigger? Fertilizer Growth of Plant Controlled Variables (What I keep the same)
Practice Question Independent Variable (What I change) Dependent Variables (What I observe) Controlled Variables (What I keep the same) Does fertilizer make a plant grow bigger? Fertilizer Growth of Plant Amount of water, soil, and sunlight
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