Packet # 4 Where does energy come from and where does it go? 4-1 What is Energy? o To recognize and describe kinetic and potential energy events. energy: the ability to make something happen potential energy: stored energy kinetic energy: energy of motion Energy is the ability to do work. Both energy and work are expressed in units of joules (J). Potential energy is stored energy. One type of potential energy is gravitational potential energy. The amount of gravitational potential energy stored in a sample of matter depends on its mass and height. Kinetic energy is energy of motion. Mechanical energy is the sum of kinetic energy + potential energy. How does a YO-YO use potential and kinetic energy? 4-2 What are different forms of energy? o To identify and describe different forms of energy. There are seven types of energy: heat (thermal), light (electromagnetic), electrical, mechanical, sound, nuclear, and chemical. The energy in moving things is mechanical energy (the sum of kinetic and potential energy). Electrical energy is in the form of moving electrons. Electromagnetic energy is a form of energy that can travel through a vacuum. Heat energy is the energy of the moving particles that make up matter. Chemical energy is the energy that holds particles of matter together. Nuclear energy is the energy stored in the nucleus of the atom. Sound energy is caused by an object s vibrations traveling through matter. What are some types of energy you can observe around you now? (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Lesson Notes, page 1
4-3 How does energy change form? o To describe examples of energy transformations from everyday life activities. Energy transformation: a change of energy from one form to another. Energy can change from one form to another. Potential energy and kinetic energy often change form. Energy transformations help to make energy useful by changing energy into the form you need. What energy transformations occur when you use a cell phone? 4-4 What is the Law of Conservation of Energy? o To recognize and describe situations that support the Law of Conservation of Energy. law of conservation of energy: energy cannot be made or destroyed, but only changed in form Because of friction, when energy changes form some of the energy always changes to heat. When waste heat energy escapes into the environment, it causes thermal pollution. The law of conservation of energy states that energy cannot be created or destroyed, but only changed in form. Einstein concluded that matter can be changed into energy, and energy can be changed into matter. Ask Mrs. Hudson what Einstein s famous equation E = mc 2 means. (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Lesson Notes, page 2
4-5 What are energy resources? o To describe energy sources and transformation of these sources in daily life. Energy resource: natural resource that can be converted into other forms of energy Nonrenewable resources: energy sources that cannot be replaced Renewable resources: energy sources that can be used and replaced Fossil fuels are nonrenewable resources formed from the remains of ancient organisms. Coal, petroleum, and natural gas are fossil fuels. Solar energy, wind energy, energy from water, and geothermal energy are renewable resources that can be replaced in nature. The sun is the source of most energy on Earth. When we burn fossil fuels, what was the source of the energy before these became fossil fuels? (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Lesson Notes, page 3
4-6 What is Heat? o To explain how heat is a form of energy. heat: energy of particles moving from warmer regions to cooler regions convection: transfer of heat through a liquid or a gas conduction: transfer of heat through direct contact between solid objects radiation: transfer of heat by waves, like heat or light. Can even happen in outer space conductors: substances that transfer heat or electricity insulators: substances that do not easily transfer heat or electricity Heat is the total kinetic energy of all the particles in a sample of matter. Heat energy moves from a warmer object to a cooler object until both objects have the same heat energy. 4-7 What is temperature? o To explain the difference between heat and temperature. temperature: measure of the average kinetic energy of the particles in a sample of matter The measure of the average kinetic energy of all the particles in a sample of matter is called temperature. Heat and temperature are related, but not the same. When you add heat energy to a substance, you change its temperature. Two samples of the same substance may have the same temperature but not the same amount of heat. (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Lesson Notes, page 4
Name Class Date 4-1 What is Energy? Concepts and Challenges in Physical Science, Teacher s Resources CD-ROM (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Energy and Work: CHAPTER 14 Lesson Notes, page 5
Name Class Date Kinetic and Potential Energy Practice Color code the following energy events in each of the 4 diagrams below o Maximum Potential Energy o Maximum Kinetic Energy o Kinetic energy being converted to Potential energy o Potential energy being converted to Kinetic energy Concepts and Challenges in Physical Science, Teacher s Resources CD-ROM (c) by Pearson Education, Inc./Globe Fearon/Pearson Learning Group. All rights reserved. Energy and Work: CHAPTER 14 Lesson Notes, page 6