1. OBJECTIVES OF TODAY’S ACTIVITY TOPIC: Buoyancy After today’s activity, you will be able to: Use the concept of buoyancy to explain how magmas rise

2. CASUAL PRINCIPLES 1.Gravitational energy, thermal energy and/or chemical energy drive all movement and change of matter on Earth. 2. A system is in equilibrium when energy in the system is balanced. 5. Temperature is a measure of the movement of molecules. Higher temperature means molecules are moving faster. 6. When molecules move faster, the density of most substances decreases. Water is anomaly because liquid water is more dense than ice. 7. Buoyancy causes materials to rise or fall due to the relative density of materials.

3. Background: Temperature and Density Temperature impacts the density of materials. Q. How does increasing temperature cause decreasing density? A. Increasing temperature causes molecules to move faster, spread out and for the density of decrease. http://blank005.tripod.com/geology/graphic/tectonic s/beaker.gif

4. Demonstration: Buoyancy Here is a video of a Galileo Thermometer: http://www.youtube.com/watch?v=917UC2MZOGU&feature= related The bubbles of different colored material have different chemical properties that mean their density changes at different temperatures. As a result, they are more or less buoyant at different temperatures.

5. Background: Buoyancy Q. What is buoyancy? A. The force that is equal to the weight of the water the object displaces. http://misclab.umeoce.maine.ed u/boss/classes/SMS_491_2003/ buoyancy.gif

6. Background: Buoyancy Q. How does buoyancy make things float? A. The density of the object is compared to the density of the fluid it is immersed in. If the object is less dense than the fluid, it will rise. http://en.wikipedia.org/wik i/File:Buoyancy.svg

7. Source: Hot Air Balloon A gas flame is used to heat the air inside the balloon. The warm air in the balloon is less dense than the air outside the balloon. Hot Air BalloonPrinciple Gas flame Differences in air inside and outside the balloon Balloon rising Balloon floating Outside air heating up during the day Amount of fuel available for the gas flame http://airpurifierreviews.info/w p-content/uploads/2010/09/hot- air-balloon-ride.jpg

8. Target: Magma Masses of hot magma rise through the lithosphere until they cool and solidify into igneous rock. MagmaPrinciple Water added to hot rocks deep underground Differences in the cold lithosphere and the hot magma Magma rising Magma solidifies and stops rising Difference between the magma and oceanic lithosphere versus continental lithosphere Gases leaving the magma http://www.mantleplumes.org/image s3/ScandesFig2_400.gif

9. Alignment: Comparing Hot Air Balloon & Magma Hot Air BalloonMagmaPrinciple Gas flame Differences in air inside and outside the balloon Balloon rising Balloon floating Outside air heating up during the day Amount of fuel available for the gas flame

10. Differences: Comparing Hot Air Balloon & Magma There are features of the hot air balloon and magma that are different. In the table fill in the aspects that are different for the causes of rising as well as the factors impacting density and buoyancy. Hot Air BalloonDifferenceMagma Factors impacting density of balloon/magma Factors impacting buoyancy

11. Group work & Homework: Buoyancy Part 2 : Alignment and Differences Work in your groups to reason out the relationship between hot air balloons and magma. Fill out the Group Worksheet to turn in at the end of class. Part 3: Homework If you complete your group work, you may start the homework. Please work on your own. This means your answers should be generally unique from other students. Turn in the homework using ANGEL.