How to Do an Experiment

There are a number of resources that describe the scientific method and how to design an experiment so that there is a single independent variable (what you change: the thing that is changed from one trial to the next) and the measurement of a dependent variable (what you measure: the thing that is measured the same way on each trial). A more involved discussion of experimental design considers the use of statistics to analyze the data.

This next description of how to craft an experiment comes by way of a science teacher who is also an amateur radio operator.

Science Fair projects should promote experimentation. For example, pull a pendulum back 5 degrees and let it swing 50 times, and find the average swing time. Now pull it back 10 degrees, then 15, then 20, etc.

Now, graph "Period" of swing on the Y axis (what you measured) and "Angle of release from vertical" (what you varied) on the X-axis. Then find a mathematical relationship.

Even more repetition is encouraged, by doing this same experiment of 5 degrees through 90 degrees, a total of 10 times, so you have 10 trials of the 5 degree swing. This makes the average (and standard deviation) more tightly constrained.

Continue Table of Contents

How to Do an Experiment
Page 1 of 3


Posted on MAY 01, 2015