Chapter 6- Heat 7th Grade Science © Fall 2005, Pflugerville ISD, 8th Grade

Unit A : Chapter 1 : Section 1 Chapter 6- Heat Section 1: What is Temperature? Section 2: What is Heat? Section 3: Matter & Heat Unit A : Chapter 1 : Section 1

What is Temperature? What Do You Think? What happens when you use a thermometer to measure temperature? Unit A : Chapter 1 : Section 1

Temperature Depends on Kinetic Energy Kinetic Energy is the energy of motion The faster the particles of matter move, the more kinetic energy they have Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Temperature? Measuring Temperature Temperature is a measure of the Average Kinetic Energy of a substance When you measure temperature, you are measuring the average motion of the atoms Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Temperature? Temperature is expressed by one of 3 scales: Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Temperature? Thermal Expansion- As temperature rises, volume increases Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Temperature? Thermal Expansion When the metal rails in this picture heated up, they increased in length and volume Thermal Expansion caused the rails to buckle and bend Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Temperature? Thermal Expansion The asphalt in the road expands when heated and contracts when cooled This results in cracks and potholes due to Thermal Expansion Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Heat- A Transfer of Energy Heat is the transfer of energy between objects or particles that are at different temperatures Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Heat- A Transfer of Energy Energy moves from the warmer object to the cooler object until both are the same temperature This is known as Thermal Equilibrium Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Reaching Thermal Equilibrium Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Energy is Transferred by 3 Methods: Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Conduction is the transfer of thermal energy through direct contact Hold a metal wire in a flame and energy travels from atom to atom until it burns your hand Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Convection Convection is the transfer of thermal energy by the movement of a liquid or a gas Convection is seen as hot material rises and cool material sinks Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 What is Heat? Radiation Radiation is the transfer of energy through matter or space as EM waves, such as visible light and infrared waves Radiation is the only type of energy transfer where the objects don’t have to touch Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat What Do You Think? When you get overheated and start to sweat, your body begins to cool off. Why? Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat States of Matter Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat Ice Crystal Particles of a solid do not move fast enough to pull apart, so they vibrate in place Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat Melting of Ice Energy must be transferred to a solid to make it become liquid The water will remain the same temperature until all of the ice has melted Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat Evaporation of Water Transfer more energy to the water and its particles move even faster When the liquid water molecules move fast enough, they become a gas Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Matter & Heat Sweat Cools You Down When your body gets too hot, you perspire The liquid sweat uses energy from your body to evaporate water molecules You get cooler! Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Let’s Review! - 1 - What is temperature? Explain what happens when you use a thermometer to measure temperature… Unit A : Chapter 1 : Section 1

How is radiation different from conduction and convection? Let’s Review! - 2 - How is radiation different from conduction and convection? Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Let’s Review! - 3 - When water evaporates, the air near the water’s surface becomes cooler. Why? Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Web Sites to Visit: Harcourt Science: States of Matter BBC: Science BrainPop: States of Matter Unit A : Chapter 1 : Section 1

Unit A : Chapter 1 : Section 1 Pre-AP Extensions You should be able to explain Thermal Conductivity and Specific Heat Capacity. You should know what a Calorimeter is and the difference between a calorie (cal) and a Calorie (C) Unit A : Chapter 1 : Section 1