Variables变数 ( school science)

Variables:

3 types of variables in an experiment:

 

1. The independent variable: is the one that you change or select.
2. The dependent variable: is the one changes as a result, and that you may measure it.
3. The control variables must not change, so that it is a fair test.

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4 other types of Variables:

There are 4 other types of variables that you may meet. 

Their names are: 

  1)Categoric 

 2) Ordered 

 3) Discrete 

  4)Continuous 

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 [1] Categoric Variables: These have word labels.

Example 1:

In this experiment on conduction of heat.

The categoric variables are: Copper, iron , glass....

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[2]Ordered Variables:

These are categoric variables that can be ranked, in an order.

Example 1: In this experiment to find the resistance of wires.

The Ordered variables could be: Thick copper wire, medium copper wire, thin copper wire.

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[3]Discrete variables:

These variables can only have whole number values, 1,2,3,4,…

Example 1: In an experiment to investigate the stretching of a spring. The discrete variables are:

1 unit of weight. 2 units of weights. 3units of weights. …

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[4]Continuous variables:

These variables can have any numerical value.

Example1: In this experiment to investigate the stretching spring.

The continuous variable is:

The length of the spring is 15.2 cm; 15.5cm,  15.8 cm, 16.1cm, …..