Energy Its all about energy Energy and its

Energy It’s all about energy. Energy and its transfer controls the Universe and Earth’s systems.

Energy The ability to do work or produce heat

Sources of Energy • Electromagnetic – Energy from the electromagnetic spectrum • Chemical – Energy released during a chemical reaction. • Nuclear – Energy released during fission or fusion

Electromagnetic Energy • Energy that radiates from the sun. • Electromagnetic spectrum (EMS) arranged by wavelength. • All EM waves travel at the speed of light. • Only difference between EM waves is wavelength.

Wavelength is the distance crest to crest of a wave.

Frequency is the number of crests that pass a given point in 1 second, (Hertz) 1 sec

Chemical Energy • Energy released during a chemical reaction. • Burning

Nuclear Fusion • Atoms fuse together to form a larger atom. • Results in a release of energy. • Sun • Hydrogen atoms fuse together to form a helium atom.

Nuclear Fission • The splitting of an atom’s nucleus into two smaller nuclei. • Results in a release of energy. • Earth’s core • Atoms decay creating heat.

It’s Fairly Simple • Earth has two sources of energy: – Radioactive decay in the core (fission) - Internal – Fusion in the sun radiates to the Earth in the form of electromagnetic energy - External • Both sources of energy are nuclear.

States of Energy • Potential – Stored energy – gasoline, snow pack, reservoir. • Kinetic – The energy of motion – flowing water, waves, landslides, thunderstorm.

Thermal Energy • Heat is thermal energy transferring from one substance to another. • Differences in temperature cause the transfer. • Matter does NOT contain heat. • Matter contains thermal energy.

Thermal Energy (cont. ) • Heat is thermal energy in transit. • After heat is transferred, it ceases to be heat and becomes thermal energy again.

Transfer of Energy • Three ways to transfer energy 1 • Conduction – the movement of heat (energy) in solids by its contact with a hotter object. – slow process (core-mantle)

Transfer of Energy 2 • Convection – the movement of heat by currents in liquids & gases because of temperature and density differences. - Fast process (air, upper mantle)

Transfer of Energy 3 • Radiation – the transfer of heat in gases or a vacuum in the form of waves. • Hot objects radiate heat. – Very fast process (infrared, ultraviolet waves)

The Laws of Energy 1. Conservation 2. Thermodynamics

Law of Conservation Energy is neither created nor destroyed it simply changes form and moves from place to place.

st 1 Law of Thermodynamics • Amount of energy going into a system has to equal the amount work, heat and byproducts coming out of a system. (i. e. heat, sound, motion, light) • The conversion is not 100% efficient. -grass for cows -gas for cars

2 nd Law of Thermodynamics • Heat flows from warmer to colder objects. • You cannot increase the amount of energy and order at the same time (Entropy). • Think of order as the motion of atoms.

rd 3 Law of Thermodynamics • Absolute zero equals absolute order. At absolute zero (-275 o. C, 455 o. F) everything freezes and atoms cease to move. • • No system can reach absolute zero.

So What

Energy drives Earth’s systems • Nuclear reactions produce energy in the sun which radiates and warms the Earth’s atmosphere and heats the surface. (External Energy) • Convection currents drive global air circulation, weather systems, and ocean currents. • Nuclear reactions also supply the heat energy to drive plate tectonics resulting in volcanoes and earthquakes. (Internal Energy) • Conduction between mantle and core brings heat to the upper mantle and convection currents drive plate tectonics.

External & Internal Energy Questions (restate the question in the answer. For example: Temperature is …. ) • Earth’s External Heat – Read pg. 548 -551 (red text) – Answer questions 1 -2 all • Earth’s Internal Heat – Read pg. 132 -135 (red text) – Answer questions 1 -3 all

The Energy Cycle

Here’s How It Works! Pressure increases Energy In Atoms move faster and get farther apart Volume decreases Temperature increases Density decreases Temperature decreases Volume increases Atoms move slower and get closer together Energy Out Pressure Decreases

Atoms • Become excited as the added energy causes electrons to jump up an energy level • They move faster and farther apart.

Temperature • Is the measure of how fast atoms are moving. • The more energy into the system the faster the atoms will move and the higher the temperature.

Density • Is the measure of the number of atoms in a given area. • The faster the atoms move and the farther apart they get the fewer there will be in the same area.

Volume • Is the space a set number of atoms occupy. • The farther apart the atoms are the more space they take up.

Pressure • Is the measure of how many atoms are pushing on a given space. • The fewer the atoms on a given space the lower the pressure.

A Note on Pressure • Pressure will decrease as long as the atoms are able to move freely. • If the atoms are contained the pressure will increase as they try to spread out. • Think of a tea kettle and a pot of boiling water. Increased pressure Decreased pressure

Energy Out • As the energized atoms come into contact with less energized atoms they transfer some of their energy to make the other atoms the same temperature. Conduction !

Equilibrium / Homeostasis • Nature wants everything to be equal and balanced. • If hot and cold water are put together what happens? • The energy is spread equally until the temperature is the same throughout. • Open a bottle of perfume. Does the fragrance stay in the bottle or diffuse?

Energy out • As the energized atoms come into contact with the less energized atoms they lose some of their energy. (conduction) • This makes the other atoms the same temperature. • Equilibrium is reached.

Atoms • Atoms slow down and get closer together. • The temperature drops. • The density increases. • The volume decreases. • The pressure increases.

ENERGY & IT’S TRANSFER DRIVES THE EARTH SYSTEMS • OCEAN CURRENTS • PLATE TECTONICS • WEATHER SYSTEMS • RADIOACTIVE DECAY

Coaster Creator Activity • Coaster Creator Web Site • Break up into Groups (groups of 4) • Discuss how to use Potential and Kinetic Energy to create a Roller coaster that balances (finds equilibrium) the energy that is stored and released during the ride. • Sketch your Rollercoaster using ramps, loops, # of cars and briefly design.

Energy Questions. 1. What is electromagnetic energy? Where does it come from? How does it travel? 2. How does energy from the sun affect the water cycle? 3. Explain how a molecule of water from the ocean can end up as precipitation in the mountains. 4. Draw the energy diagram. Then explain how each factor works. 5. Describe in detail exactly what causes warmer gasses and liquids to rise, and cooler gasses and liquids to fall. What Kind of energy transfer is this? 6. Explain what equilibrium is and then give an example of it found in nature.

External & Internal Energy Questions • Earth’s External Heat – Read pg. 548 -551 (red text) – Answer questions 1 -2 • Earth’s Internal Heat – Read pg. 132 -135 (red text) – Answer questions 1 -3