Scientists aren’t perfect, and sometimes they may realize after completing an experiment that there is some aspect of the experiment that could have been improved. Other times, the results of the experiment may inspire scientists to conduct a new, modified version of the original experiment. Modify questions may ask students to infer the results if another variable was added to the experiment, or ask the best way to alter the experiment to observe the effect of a certain variable. Hypothesis questions are grouped into this category, since you will be creating your own hypothesis as to what will happen with the altered experiment.
Below is a sample passage from the ACT Science section that features Modify questions. We will reference this passage when attempting to answer the questions.
The following Modify question deals with altering the experiment in some way.
This question asks you to modify the procedure of the experiment in a way that would best test whether the amount of heat created by SF is related to the mass of the SF.
Therefore we want the independent variable to be the mass of the SF, and the dependent variable to be the heat generated, since we are trying to figure out if the mass affects the heat generated.
Study 1 and Study 3 both measure rock temperature increase, which shows the heat generated.
However, Study 3 is measuring the temperature increase of different rock types over a period of 100,000 years. Study 1 is measuring the rock temperature after 1 year, with a controlled mass of 0.4 metric tons of SF in each canister.
Since Study 1 controls the mass, we could observe the effect of the mass by keeping the same conditions of Study 1, but change the mass of the SF.
Therefore, the answer is F.