THERMAL ENERGY Chapter 5

TEMPERATURE, THERMAL ENERGY, AND HEAT – 5.1 A. Temperature 1. Matter in motion 2. Kinetic energy and temperature a. Please Define Temperature: Measure of the average kinetic energy of all the particles that make up an object.

B. Thermal Energy 1. Please Define Thermal Energy: Sum of the kinetic and potential of the particles that make up an object.

2. Temperatures and thermal energy 3. Mass and thermal energy C. Heat 1. Please Define Heat: Energy that is transferred between objects due to a temperature difference between those objects.

1. Please Define Specific Heat: Amount of heat needed to raise D. Specific Heat 1. Please Define Specific Heat: Amount of heat needed to raise the temperature of 1 kg of a material 1oC.

2. Water as a coolant 3. Calculating thermal energy changes

Practice Problems p. 142 1. 2. 3.

F. Measuring Specific Heat 1 F. Measuring Specific Heat 1. How does the Calorimeter measure the specific heat of a substance? The scientists heats a sample of matter, measures the sample’s temperature change, its mass, and how much energy was transferred from the sample of matter to water inside the Calorimeter.

CONDUCTION, CONVECTION, AND RADIATION – 5.2 A. Conduction 1. Please Define Conduction: Transfer of thermal energy by collisions between the particles that make up matter.

2. Collisions transfer thermal energy

3. Thermal conductors a. Name three excellent conductors: 1. Silver 2 3. Thermal conductors a. Name three excellent conductors: 1. Silver 2. Copper 3. Aluminum

1. Please Define Convection: Transfer of thermal energy in a fluid B. Convection 1. Please Define Convection: Transfer of thermal energy in a fluid by the movement of warmer and cooler fluid from one place to another.

2. Convection currents a. How does convection occur 2. Convection currents a. How does convection occur? The rising of a heated fluid and at the same time the falling of a cooling fluid.

3. Deserts and rainforests

Radiation 1. Please Define Radiation: The transfer of heat by electromagnetic waves.

2. Radiation and matter 3. Radiation in solids, liquids, and gases

D. Controlling Heat 1. Animals and heat

E. Thermal insulators 1. Please Define Thermal Insulator: A material through which thermal energy moves slowly.

a. Why is fleece a “good” insulator? 2. Insulated clothing a. Why is fleece a “good” insulator? The fibers in the fleece trap the air and hold it next to you. The air slows the transfer of your body’s thermal energy into its surroundings. Under the jacket, a blanket of warm air covers you.

a. Why is fiberglass a “good” insulator? 3. Insulated buildings a. Why is fiberglass a “good” insulator? The fiberglass insulation contains fluffy material that contains pockets of trapped air which slows the transfer of heat to the surroundings.

a. Why are Thermoses “good” insulators? There is a vacuum between the two surfaces of a thermos bottle. This minimizes the transfer of thermal energy by conduction and convection. Thermos bottles also have reflective surfaces, which minimize energy transfers by radiation.

USING THERMAL ENERGY – 5.3 A. Heating Systems 1. Forced-air systems

2. Radiator systems

3. Electrical heating systems

a. Passive solar heating 1. How do Passive solar heating systems work? In passive solar heating systems, materials inside a building absorb radiant energy from the Sun and heat up during the day. At night when the building begins to cool, thermal energy absorbed by these materials helps keep the room warm.

b. Active solar heating 1. What is a solar collector b. Active solar heating 1. What is a solar collector? Device used in an active solar heating system that transforms radiant energy from the Sun into thermal energy.

1. Please Define Thermodynamics: Study of the relationship between thermal energy, heat, and work.

2. Heat and work increase thermal energy

3. The first law of thermodynamics a. Please Define the First Law of Thermodynamics: States that if the mechanical energy of a system is constant, the increase in the thermal energy of the system equals the sum of the thermal energy transferred into the system and the work done on the system.

4. Isolated and non-isolated systems

5. The second law of thermodynamics a. Please Define the Second Law of Thermodynamics: States that energy spontaneously spreads from regions of higher concentration to regions of lower concentration.

Converting Thermal Energy into Mechanical Energy 1. Heat engines a. Please Define Heat Engine: Device that converts some thermal energy into mechanical energy.

2. Internal combustion engine a. Please Define Internal Combustion Engine: Heat engine that burns fuel inside the engine in chambers or cylinders.

Doing Work to Transfer Thermal Energy 1. Refrigerators

Doing Work to Transfer Thermal Energy 2. Air conditioners

Doing Work to Transfer Thermal Energy 3. Heat pumps

Doing Work to Transfer Thermal Energy 4. Energy transformations and thermal energy a. Friction converts mechanical energy into thermal energy when electrical generators rotate.

Doing Work to Transfer Thermal Energy 4. Energy transformations and thermal energy b. A laptop computer converts electrical energy into thermal energy.

A. Please do Check Concepts 29-35 on page 164 in your Text. CHAPTER 5 REVIEW A. Please do Check Concepts 29-35 on page 164 in your Text. B. Please do Standardized Test Practice 1-8 on page 166 in your Text. C. I will type out a Pre-Test with an Equation sheet for you to practice before your Test on Chapter 5.