Experimental Design - Variables A factor or condition that can change during an event or investigation

Identifying Variables List four variables that exist for each situation: Ex: What variables can affect the sprouting of a plant seed? 1. amount of water received 2. amount of sunlight 3. amount of fertilizer 4. age of the seed

Practice (List four for each) What variables can affect the attendance at a new movie? What variables can affect how many pizzas a restaurant sells? What variables can affect the speed of an airplane? What variables can affect the amount of fruit produced by an apple tree? What variables can affect the amount of rain an area receives?

Experimental Design - Variables 3 Types: Independent (I.V.) Dependent (D.V.) Constant (C.V.) The factor you ‘choose’ to study; what do you make ‘different’ The factor that is affected by the experiment; what do you ‘measure’ The factors that are kept the same; what was kept the ‘same’

Practice List the independent, dependent, and constant variables for each situation: Ex: Students of different ages were given the same puzzle to assemble. The puzzle assembly time was measured. Independent = different ages of students Dependent = assembly time Constant = same puzzle

Indentifying Variables List the independent, dependent, and constant variables A study was done to find if different tire treads affect the breaking distance of a car. A study was done to measure the cleaning effectiveness of different brands of dishwashers. They all had the same water source. A study was done to see how the length of the blades of helicopters affected their maximum flying speed.