Science help? independent variables? and dependent variables?

Question

I'm doing a lab experiment and having trouble. If I cut an apple into 4 halves, and I put them all in cups, then I set two of the cups in the fridge and two out on the counter. I then sprinkle lemon juice on one apple in each group and let them stand for 4 days. What is my independent variable and what is my dependent variable, very confused?

Answer 1

The lemon juice is independent. The others are dependent cause it was added to the original facts.

Answer 2

An independent variable (IV) is something you manipulate as an experimenter. In this situation there are two different IV's, each with two levels. The first IV is environment, with two levels, counter and fridge. The second IV is lemon juice, with two levels, lemon just and no lemon juice.

Since all pieces were cut equally and put into the same cups, this is just a control factor, and NOT a variable (it is consistent and does not vary).

As for a dependent variable (DV) I don't see one listed in your question, but I'm guessing it would be preservation level, or coloration. Keep in mind a dependent variable is something we measure at the end of an experiment. Looks like this experiment is trying to see what the best way to preserve apple slices is, so you'll need to find a way to define and measure this.