Meaning
A variable is something that you can change, keep the same, or measure/observe in an investigation.
About Variables
- There are three types of variable.
Examples
An investigation to test the claim: All leaves are green.
| Oak Leaf
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Beech Leaf
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Ash Leaf
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| Maple Leaf
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Chestnut Leaf
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Variables
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- The different leaves chosen was the independent variable.
- The colour of the leaves was the dependent variable
- The experiment was done at the same time of year for every tree because at different times leaves can change colour or fall off. This was a control variable
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| Results Table
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Variables
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- The type of food chosen was the independent variable.
- The colour of the iodine after being added to food was the dependent variable.
- There are many control variables that should be done. If the food colour was blue or black it might give the wrong result, so all the food should be the same pale colour. Another control variable is the amount of iodine used.
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| Experiment
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Variables
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| Cress seeds were put in pots with soil with half placed in a dark cupboard and half on a windowsill.
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- Independent Variable: Where you chose to put the cress seeds.
- Dependent Variable: The observations of the cress seeds.
- Control Variable: How long you left them for. They should all be left for the same amount of time or it's not a fair test.
- Control Variable: How much you watered them. They should both be watered the same amount to make it a fair test.
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