Controlled variable ##rArr## have nothing done to it. Constant variable ##rArr## kept the same Dependent variable ##rArr## you observed/measured Independent variable ##rArr## changed

Lets take this scenario, you want to find out how the volume of water watered can affect the growth of the bean sprouts .

So you have 2 pots for this experiment, Pot A and Pot B. With Pot A having a usual volume of ##50ml## watered every time, and Pot B having a higher than usual volume of ##100ml## watered every time.

Independent Variable: The variable that you changed.

• In this case is the volume of water watered .

Dependent Variable: The variable that you observed/measured.

• In this case is the height of the bean sprout .

Constant Variable: The variable that is kept the same throughout the experiment.

• In this case are:

• Type of Pots used

• Number of Seeds planted
• Temperature of the surroundings
• Time at which the plants are watered

Of course, there are other variables that should be kept constant, the above 4 are just examples.

Controlled Variable: The variable that have nothing done to it.

• In this case it refers to Pot A , which is the usual pot, no independent variable existed as the volume of water have no change (usual ##50ml##).