Energy What is Energy Energy What is energy and how it is The ability to do work and like measured? work it is also measured in joules. The sum of all energy, potential and kinetic within a specific What is mechanical energy? system. It is the total amount of energy that an object has due to its position, orientation (if it’s stretched or compressed) and its motion. Mechanical Energy Machines will convert one to another in order to do work. Energy What are some of the forms of energy? Potential Kinetic Sound Solar (light) Thermal (heat) Electrical (STORED) (MOTION) Energy What are some other forms of energy? Chemical Elastic Gravitational Nuclear Electromagnetic Energy can not be created or destroyed, it can only change forms Energy What is potential energy? It is stored energy. Energy is stored by doing work against a force and waiting to be used. Potential energy is due to position or chemicals. The higher the object is, the greater its potential energy. Forms of Potential Energy What is chemical potential energy It is the energy that is stored in and some examples? the bonds and attractions within and between the atoms of molecules. When a substance undergoes a chemical reaction, chemical potential energy is released. Examples include food for organisms, fossil fuels that can burn, hydrogen, and batteries. Forms of Potential Energy What is elastic potential energy It is the energy that is the results and some examples? from stretching or compressing an object. Examples include springs, rubber bands, and other elastics objects. When a spring is stretched, work has been done to deform the spring, resulting in increased potential energy. Forms of Potential Energy What is gravitational potential It is potential energy that is energy and some examples? related to an objects height above ground. It directly proportional to the object’s mass, height, and the acceleration due to gravity. When two object’s mass are equal, the object with the greater height has the greater gravitational potential energy. Example are anything that can fall to include ski jumpers, planes and climbers. Examples of Potential Energy Gravitational potential energy increases as weight and height increase Forms of Potential Energy Kinetic and Potential Energy cartoons!! Energy What is kinetic energy? It is the energy that an object has due to its motion. It can be harnessed and transformed into other kinds of energy. The amount of kinetic energy an object has is related to its mass and velocity. The greater the velocity and mass of an object, the more kinetic energy it has. Kinetic energy increases as mass and velocity increases. Forms of Kinetic Energy What is radiant (light) energy and It is energy that is transmitted in some examples? the form of electromagnetic waves. Radiant energy does not need a medium to travel through. Examples include visible and infrared light form the sun, human-made objects that emit radiant energy to include light bulbs and street lights. Glow worms are organisms that produce light energy. Forms of Kinetic Energy What is thermal (heat) It the energy of an object due to energy and how is it used? random motion of its particles. The faster the particles move, the greater the thermal energy and temperature. Heat is transferred from warmer to colder objects. Anything above absolute zero (-2730 C) has heat energy. Heat energy can be produced from matter that undergoes a chemical change or from another form of energy. It helps produce electricity, steam, and boils water. Forms of Kinetic Energy What is sound energy and how It is the form of energy that is does it travel? carried by sound waves as they travel through a medium, such as air. Sounds are produce by vibrating objects and travel through various materials. The speed depends on what it is traveling through. Examples includes anything noisy It travels more quickly through that gives off sound energy like more elastic substances. It vocal chords, speakers, and travels faster in water than air and instruments. cannot travel through a vacuum such as outer space. Forms of Kinetic Energy What is electrical energy and It is the energy associated with where can we find it? charged particles such as electrons. When the particles are moving or flowing in a current, the energy is electricity. It travels through conducting materials like wires. Electrical energy is very useful, because it can be generated from other types of energy and transported to new locations. It Some items to produce it include can be transformed into heat, batteries, solar cells, generators, light, sound, or mechanical flowing water, moving air, and burning fossil fuels. energy. Converting Forms of Energy A C D E B A B C All potential energy All kinetic energy All potential energy (stops for an instant) (greatest speed) (stops for an instant) P.E. = 10 J K.E. = 10 J P.E. = 10 J K.E. = 0 J P.E. = 0 J K.E. = 0 J D E Potential energy & Potential energy & Kinetic energy Kinetic energy P.E. = 5 J; K.E. = 5 J P.E. = 4 J; K.E. = 6 J How to Measure Energy • Kinetic Energy • KE = ½mv2 • Potential Energy • PE=mgh (mass (x) gravity (x) height) gravity=9.8m/s2 • Temperature • Thermometer • Joules=1kg m/s2 Other forms Energy What are some other forms of Nuclear Energy is release only energy? from nuclear reactions e.g. the sun and all of the stars. Hydrogen bomb (Fusion) and Nuclear power plants and the Atomic bomb. (Fission) All of this energy comes from mass of atoms. Wind energy is an exhaustible resource that comes form the movement of air heated by the sun. Hydroelectric Energy is electrical energy converted from kinetic energy of falling water. Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Use information you’ve learned to respond to the following question. Use evidence from your resources to support your response. Answer: Evidence to support my answer: Energy Transformation What is Energy The process in which energy Transformation? changes from one form to another. Energy is constantly being transformed. versa. Energy Transformation What is the Law of Conservation It states that the total amount of Energy? of energy in a system remains constant. Energy can be converted from one form to another, but it cannot be created or destroyed. It can only move from one object to another or change from one kind or form of energy to another , such as when energy changes from potential to kinetic and vice versa. Law of Conservation of Energy - Rules Energy going in is ALWAYS EQUAL to energy coming out. There is ALWAYS WASTED ENERGY during any transfer. In most cases the wasted energy is usually heat and so most energy transformations include heat. Energy is Never Transformed 100% Engines do not transform 100% of the chemical energy from gasoline into kinetic energy. Bicycles do not transform 100% of the energy from the biker into motion. Energy is NOT “lost”, it’s just transformed to heat. Energy Transformation - Examples Chemical energy in food is converted to thermal energy and kinetic energy by our bodies. Gravitational energy in a ball is converted to kinetic energy when it falls to the ground. change from chemical energy to radiant, acoustic, or electrical energy change from kinetic energy to potential energy change from nuclear energy to light, chemical, or mechanical energy change from almost any other form of energy to heat energy Energy Transformation - Examples ✴ burning match • chemical to heat and light ✴ portable torch • chemical to heat and light ✴ microphone • sound to electrical ✴ radio • electrical to sound and heat ✴ television • electrical to sound and light and heat ✴ catapult • elastic to kinetic and heat ✴ cell phone • chemical to sound and microwaves (EM radiation) and heat ✴ car • chemical to kinetic and sound and heat In all these transfers the energy is not lost, it is conserved. The Law of Conservation of Energy states: Energy cannot be destroyed or created only change forms. Heat and Energy Transformations What happens in the Ex. Some of the energy of an transformation? exploding star radiates through space as heat. Some of the stored chemical energy in the human body converts to heat when it is released to help grow new living cells or to make the body move. Energy can also be lost as heat during transfer of the same type of energy, i.e. the moving gears of a machine lose heat energy due to friction as mechanical motion is transferred from one gear to another. Heat and Energy Transformations Here is an example of heat and energy transformation.