Question

If there are many variables in an experiment that can affect the dependent variable in a question, what do you, as an experimenter, need to do for the experiment to be considered valid?

A) You can change all of the variables for any given trial; you just need to keep track of them.
B) You need to keep our variables constant in value except for the independent and dependent variables.
C) Keep all the variables constant in the experiment.
D) Keep none of the variables constant in the experiment.

Answer 1

In an experimental study, to achieve valid results, you need to keep all variables constant except for the independent and dependent variables, so you can clearly assess the effect of the independent variable on the dependent variable.

Step-by-step explanation:

To conduct a valid experiment and ensure that the results are reliable, as an experimenter, you need to keep all variables constant except for the independent and dependent variables. This means you should only manipulate the independent variable and measure how it affects the dependent variable, while all other potential variables that could influence the outcome must be controlled or held constant. This allows you to attribute any changes in the dependent variable directly to the manipulation of the independent variable, without interference from other variables. Therefore, the correct answer is B) You need to keep all variables constant in value except for the independent and dependent variables.

For example, if you're conducting an experiment on how the type of fertilizer affects plant growth, the independent variable would be the type of fertilizer and the dependent variable would be the plant growth. All other factors, such as amount of sunlight, water, and type of plant, would need to remain constant to conclusively determine the effects of the fertilizer.