ECS UNIT 1

What is an independent variable?

• What a scientist changes in an experiment to test their hypothesis

• What scientist measure to see if it responded to a change

• What happens when you do an experiment

• What you keep the same throughout all experimental groups

What is an dependent variable?

• What a scientist changes in an experiment to test their hypothesis

• What scientist measure to see if it responded to a change

• What happens when you do an experiment

• What you keep the same throughout all experimental groups

Mr. S. sets up an experiment to see how the mass of a ball affects the distance it rolls off a ramp.  Identify the independent variable.

• distance traveled by the ball
• height of the ramp
• mass of the ball
• weight of the ball

What are all the things that are kept the same in an experiment?

• control variables

• data
• constant

• independent variables

Students wanted to see if the type of material effected the temperature after being placed under a heat lamp for 10 minutes.  
What is the dependent variable for this investigation? 

• Type of material (rocks, sand etc)
• Temperature after 10 minutes
• Time under the lamp
• Heat lamp, amount of material

1. Place 20 spinach leaves into the container
2. Put the carbon dioxide sensor in and close       the container 
3. Turn on the light and wait 20 minutes 
4. Check the carbon dioxide levels 
5. Repeat experiment with different amounts of time under the light 
What is the dependent variable?

• Amount of Light
• Amount of Spinach
• Distance from the light 
• Amount of Carbon Dioxide

Blue Color: Chemical or Physical Property

• Chemical Property
• Physical Property

Density: Chemical or Physical Property

• Chemical Property
• Physical Property

Flammability (burns): Chemical or Physical Property

• Chemical Property
• Physical Property

Reacts with Acid: Chemical or Physical Property

• Chemical Property
• Physical Property