THE HEAT IS ON!!!!!!!!!! What is Heat? • Heat is the flow of energy from one place to another. • Heat always flows from warmer objects to cooler objects. Sun Land The Sun: Our Main Source of Heat • The sun is our main source of heat here on Earth. • Heat from the sun travels through the air until it reaches our skin. This warms us up!!! A Little Fuel on the Fire • A fuel is anything that can be burned to produce heat like wood, oil, coal, or gas. • Some fuels are fossil fuels. • Fossil Fuels- formed millions of years ago from the remains of ancient plants and animals– coal, natural gas, and oil • Fossil fuels are nonrenewable resources from the Earth. When they’re gone, they’re gone. More Sources of Heat • Electricity produces heat. It also powers machines that produce heat. • Friction- two materials rubbing together (like your hands on a cold day!!!!) What Materials Transfer Heat? • Materials that transfer heat well are called conductors. • Metals like copper, iron, silver, and aluminum are examples of conductors. What Materials Do Not Transfer Heat Well? • Materials that do not transfer heat well are called insulators. • Examples: wood, plastic, cloth, rubber Heat in the Kitchen Where is the conductor and insulator located on this frying pan? Three Ways Heat is Transferred • Conduction—the transfer of heat energy between two objects that are touching. Three Ways Heat is Transferred • Convection—the transfer of heat energy through a fluid like a liquid or gas. Three Ways Heat is Transferred • Radiation—the transfer of heat energy through space or air. How Does Heat Affect Size? • Most matter expands, or gets larger when heated. • When matter cools, it contracts, or shrinks. * Remember what the physicist showed you on Career Day with the brass ball and brass ring? People Keep Warm By… • Wearing layers of clothing to form insulation • Rubbing hands together • Building a fire People Keep Warm By… • Turning on a heater • Sitting near the sunlight • Using an electric blanket