Identifying Variables Created by L. Watson September 2013 JT Foster and New Brigden Schools

Types of Variables There are 3 main types of variables: Independent Variable: The variable that is changed by the scientist. Dependent Variable: The variable that might change because of what the scientist changes The dependent variable is what is measured. Another way to think of it is what change is observed. Controlled Variables: All other variables in the experiment are kept EXACTLY THE SAME. They do not change at any time in the experiment or else your results will be void.

Practice #1 How much water flows through a faucet at different openings? Independent Variable? Dependent Variable? IV: Water faucet opening (closed, half open, fully open) DV: Amount of water flowing measured in liters per minute

Practice #2 How does the voltage of an AA battery change over time when used in low, medium, and high current drain devices? Independent Variable – Time (how long each battery operates in a given device) Dependent Variable – Voltage

Practice #3 A scientist wants to see if the brightness of light has any effect on a moth being attracted to the light. Independent Variable Lights brightness Dependent Variable How the moth reacts to the different light levels

Assessment So you have finished up our lesson. Now please go to the image below (back on the homepage) and download the practice page and then ‘Despicable Me’ practice pages. When you have finished them, please turn them into me so we can review them together. After you have finished ‘Despicable Me’, you will now complete your final project to show me that you have mastered this outcome. Click on the “Performance Assessment” link and work through your final project. Good luck!