Energy, Heat and Heat Transfer

1. Energy, Heat and Heat Transfer Earth Science Intro Unit

2. I will be able to describe Energy and the two types of energy. What is Energy? • Energy • Is the ability to cause change • Many forms of energy • Two general forms of energy are • Kinetic energy • Potential energy

3. I will be able to describe Energy and the two types of energy. What is Kinetic Energy? • Kinetic Energy • Is the energy of an object that is due to motion • All moving objects have kinetic energy • All particles in matter are in constant motion • The faster the particles move the more kinetic energy they have

4. I will be able to describe Energy and the two types of energy. What is Kinetic Energy? • Kinetic Energy • Depends on mass and speed. • Increases as mass increases • Increases as speed increases

5. I will be able to describe Energy and the two types of energy. What is Potential Energy? • Potential Energy • Energy an object has due to its position and condition.

6. I will be able to describe Energy and the two types of energy. What is Potential Energy? • Potential Energy • Examples: • A ball held above the ground has potential energy because the force of gravity can pull it down. • Stretching a rubber band increases its potential energy because of its condition.

7. I will be able to describe how particles of matter move in each state of matter. How do particles move? • Solids • Held tightly together • Vibrate in place • Liquids • Move more freely • Slide/tumble over each other. • Gas • Particles far apart. • Move at high speeds • Collisions occur.

8. I will be able to define and describe temperature, thermal energy and heat. How does temperature relate to kinetic energy? • Temperature • Measure of the average kinetic energy of all particles. • Absolute Zero • Temperature at which the motion of particles stop. • Not possible to reach it.

9. I will be able to define and describe temperature, thermal energy and heat. How does temperature relate to kinetic energy? • Temperature • Cooler Liquids • Move Slower • Lower Temperature • Warmer Liquids • Move faster • Higher Temperature • Example: Hot Iron • Particles in the solid are vibrating very fast. • Has a high average kinetic energy.

10. I will be able to define and describe temperature, thermal energy and heat. How is Temperature Measured? • Thermometer • An instrument used to measure temperature. • Units: • Celsius (˚C) • Fahrenheit (˚F) • Kelvin

11. I will be able to define and describe temperature, thermal energy and heat. What are the Temperature Scales?? • Most commonly used Water Boils Body Temp Room Temp Water Freezes • Used by physics • Kelvin not degrees • Lowest temp = absolute zero • Used mostly in the US

12. I will be able to define and describe temperature, thermal energy and heat. What is Thermal Energy? • Thermal Energy • Total kinetic energy of all particles in a substance. • SI System Unit • J (joules)

13. I will be able to define and describe temperature, thermal energy and heat. How is Thermal Energy different from Temperature? • Difference? • Temperature = average kinetic energy. • Thermal Energy = total energy • Example: • A lake and glass of water can have the same temperature. • A lake has more molecules so it has more thermal energy.

14. I will be able to define and describe temperature, thermal energy and heat. How is Heat? • Heat • Is the energy transferred from an object of a higher temperature to an object of a lower temperature. • Always flows from hot to cold. • More energy to less • Three ways it is transferred Hot to Cold

15. I will be able to define and describe temperature, thermal energy and heat. How is heat related to thermal energy? • Heat / Thermal Energy • Heat is the energy involved when properties change. • Temperature and thermal energy are properties of a substance. • Adding or revolving heat with affect its: • Temperature • Thermal Energy

16. I will be able to define and describe temperature, thermal energy and heat. How can heat affect the state of an matter? • Heat / State of Matter • State of a substance depends on the speed of the particles. • Adding / removing heat can result in a change of state. • Example: • Adding heat to ice cube changes it from a solid to a liquid

17. I will be able to compare and contrast the three types of energy transfers. How can heat be transferred? • Energy Transfer Stations Station 2 Station 3 Station 1

18. I will be able to compare and contrast the three types of energy transfers. How can heat be transferred? • Radiation • Transfer of energy as heat by electromagnetic waves. • Radio waves, microwaves, infrared waves visible light, ultraviolet waves. • Can travel through empty space. • Cannot see it, but feel it as heat (infrared) • Sunlight • Open Fire • Living things

19. I will be able to compare and contrast the three types of energy transfers. How can heat be transferred? • Conduction • Transfer of energy as heat by direct contact. • Occurs when objects of different temperatures come in contact. • Particles bump into each other transferring their energy. • Continues until the temperatures are equal. • Can occur with a single object. • Energy is transferred from the warmer part to the cooler part.

20. I will be able to compare and contrast the three types of energy transfers. How can heat be transferred? • Convection • Transfer of energy as heat by the movement of a liquid or gas. • In most substances, as temperature increases, density decreases. • Convection occurs when a cooler (denser) fluid (liquid or gas) replaces a warmer (less dense) mass of a fluid. • Creates a convection current.

21. I will be able to explain how convection transfers heat energy. How a Convection Current Works? • Warmer Fluids • Particles move faster. • Particles spread out increasing volume • Density becomes less dense, and fluid rises. • Cooler fluids • Particles move slower • Particles come together, decreasing volume. • Density increases, fluid sinks.