contols in experiment (1 Viewer)

[sneeky pete]

hey im trying to understand practicals, i get the idea that a variable is something u keep constant such as air pressure, and that a control is eg, when doing a ph experiment for example the control is distilled water(slightly acidic, hydronium ions) yeah a bit of chem. but what about an experiment measuring the life of a battery as we did in yr 10? the variables would be to have the same resistance and type of batteries but what would the control be?

 

[helper]

Variables are anything that effect an experiment. There are three types:

Independent: The thing you are changing.
Dependent: The thing you are looking for a change in
Controlled: The variables you will keep the same. Should be everything except the first two but in practice this can be hard to do. The ones you can't keep the same but should are reported in your discussion.

The control is the set up you are comparing your results against.
From what you are saying, you would choose one type of battery to be the control and compare against it.

 

[Forbidden.]

It seems you are doing Mathematics Extension 1 & 2 you should have no trouble what I'm trying to say.

I pretend that the variables-
Independent: x
Dependant: y or f(x)

Let's say you graph voltage versus current of an ohmic-device.
Voltage = Current
or
y = x
or
f(x) = x

x, the independant variable can be changed according to your likes but y or f(x) the dependant variable depends on x.