Thermal Energy Day 2 Materials Needed: Writing Utensil Writing Utensil Notebook Notebook Folder Folder Please grab a handout!!

1. Are particles located closer together in a solid or a liquid? 2. Would you be warmer sitting next to a window with the sun coming in or next to the wall? Agenda Notes over processes of thermal energy transfer.

Q1: W HY IS THE LIGHT FROM THE FLASHLIGHT BRIGHTER AT POINT A THAN AT POINT B? A. Light can travel only in a vacuum. B. Light reflects off the flashlight. C. Light energy is spread over a larger area. D. Light slows down between points A and B. SC8.2.3.c DOK 1

Q2: N EEDLES MADE FROM WHAT MATERIAL WOULD MAKE THE MOST RELIABLE COMPASS ? A. cardboard B. metal C. paper D. plastic SC8.4.2.d DOK 1

Write the expression for a number (x) that is increased by ¼of itself.

G REEK & L ATIN Greek /LatinMeaningExample flex-bend tetra-Four calor-heat bi-two phon-sound

O BJECTIVES T HERMAL E NERGY D AY 2 I will know the process of transfer of thermal energy or heat. I will know the three laws of thermodynamics. I will be able to identify the process of transfer of thermal energy.

1. Are particles located closer together in a solid or a liquid? particles are closer in a solid 2. Would you be warmer sitting next to a window with the sun coming in or next to the wall? the sun would make you warmer

A1: W HY IS THE LIGHT FROM THE FLASHLIGHT BRIGHTER AT POINT A THAN AT POINT B? A. Light can travel only in a vacuum. It is not the material that causes the light to dim from point A to point B. B. Light reflects off the flashlight. Reflection of light off the flashlight has nothing to do with the light dimming from point A to point B C. Light energy is spread over a larger area. The light becomes more spread out as the distance from the source increases. D. Light slows down between points A and B. It is not the speed of light in air that causes the light to dim from point A to point B. SC8.2.3.c DOK 1

A2: N EEDLES MADE FROM WHAT MATERIAL WOULD MAKE THE MOST RELIABLE COMPASS ? A. cardboard Cardboard is unable to be magnetized. B. metal Metal is able to magnetized thus it would point towards the North Pole. C. paper Paper is unable to be magnetized. D. plastic Plastic is unable to be magnetized. SC8.4.2.d DOK 1

Write the expression for a number (x) that is increased by ¼of itself. X + ¼ of x = x + + =

Types of Thermal Energy Transfer Three main types of energy transfer o Conduction o Convection o Radiation

Conduction is the transfer of thermal energy with no overall transfer of matter. Conduction occurs within a material or between materials that are touching. In conduction, collisions between particles transfer thermal energy, without any overall transfer of matter.

The arrows show how thermal energy is conducted away from the heat source in a metal frying pan. Thermal Conductors A thermal conductor is a material that conducts thermal energy well.

Why does the handle of a meal pan get hot? Metals are good thermal conductors. When a frying pan is on a hot stove, the bottom of the metal pan heats first and the metal handle last. The flames do not directly heat the handle. Does a tile or wood floor feel colder? Tile is a better conductor than wood. A tile floor feels colder than a wooden floor when both floors are at room temperature. The tile transfers thermal energy more rapidly away from your skin. Conduction – talk with a partner

Thermal Insulators A material that conducts thermal energy poorly is called a thermal insulator. Air is a very good insulator. Wool garments and plastic foam cups use trapped air to slow down conduction.

Convection is the transfer of thermal energy when particles of a liquid or gas move from one place to another. In what natural cycles do convection currents occur? ocean currents, weather systems, and movements of hot rock in Earth’s interior.

A convection current occurs when a fluid circulates in a loop as it alternately heats up and cools down. Air at the bottom of an oven heats up, expands, and becomes less dense. The hot air rises. Rising hot air cools as it moves away from the heat source. As a result, the coolest air is at the top of the oven Convection

Radiation Radiation is the transfer of energy by electromagnetic waves moving through space. Does an object’s temperature affect radiation? Yes, as an object’s temperature increases, the rate at which it radiates energy increases.

The sun warms you by radiation on a clear day. The space between the sun and Earth has no air to transfer thermal energy. Heat lamps used in restaurants are another example of radiation. Radiation

Thermodynamics is the study of conversions between thermal energy and other forms of energy. There are three laws of thermodynamics.

Energy cannot be created or destroyed, but it can be converted into different forms. Added energy increases the thermal energy of a system or does work on the system. In either case, energy is conserved. Thermodynamics First Law of Thermodynamicsstates that energy is conserved.

Thermal energy flows spontaneously only from hotter to colder objects. A refrigerator must do work to transfer thermal energy from the cold food compartment to the warm room air. The thermal energy is released by coils at the bottom or in the back of the refrigerator. Thermodynamics Second Law of Thermodynamics states that thermal energy can flow from colder objects to hotter objects only if work is done on the system.

Fun Fact: This physicist uses a laser to cool rubidium atoms to 3 billionths of a Kelvin above absolute zero, the closest scientists have been able to get to absolute zero. Thermodynamics Third Law of Thermodynamics states that absolute zero cannot be reached.

Turn to your neighbor Between you and your neighbor, list the three laws of thermodynamics. Next, try to break down the word ‘thermodynamics’ into its roots. What do all the roots mean? thermo – heat dynamic – power thermodynamics = heat power

Group Practice 1. Complete the table, providing an explanation for each of the picture, providing an example and two non- examples. 1. Complete the questions by indicating if convection, conduction, or radiation is present in the situation.

Independent Practice What form of energy transfer requires the motion of particles of a fluid (liquid or gas)? a. conduction b. convection c. radiation d. insulation

Independent Practice What form of energy transfer requires the motion of particles of a fluid (liquid or gas)? a. conduction b. convection c. radiation d. insulation ANS:B

Independent Practice What happens in every case in which energy is added to a system? a. Temperature increases. b. Work is done on the system. c. All of the energy can be accounted for as work or heat. d. An identical amount of energy is removed from the system.

Independent Practice What happens in every case in which energy is added to a system? a. Temperature increases. b. Work is done on the system. c. All of the energy can be accounted for as work or heat. d. An identical amount of energy is removed from the system. ANS:C

Independent Practice Thermal energy can move from a cooler object to a warmer object when a. the warmer object is larger. b. the cooler object has more thermal energy. c. energy is transferred by radiation. d. work is done on the system.

Independent Practice Thermal energy can move from a cooler object to a warmer object when a. the warmer object is larger. b. the cooler object has more thermal energy. c. energy is transferred by radiation. d. work is done on the system. ANS:D

Independent Practice All metals are good thermal insulators. True False

Independent Practice All metals are good thermal insulators. True False ANS:False, conductors

Independent Practice How is a room heated by an electric baseboard heating system? a. conduction and convection only b. conduction and radiation only c. convection and radiation only d. conduction, convection, and radiation

Independent Practice How is a room heated by an electric baseboard heating system? a. conduction and convection only b. conduction and radiation only c. convection and radiation only d. conduction, convection, and radiation ANS:C

1. What are the three ways the heat or thermal energy travels? 2. What will the final temperature be when a hot liquid and a cold liquid are mixed?

1. What are the three ways the heat or thermal energy travels? Conduction, Convection, and Radiation. 2. What will the final temperature be when a hot liquid and a cold liquid are mixed? The final temperature of the liquid will be higher than the cold liquid, and lower than the original hot liquid.

Complete the Heat Cross Word Puzzle