Law of Energy Conservation Mr. Heath Blue Creek Elementary School

Before We Start… Open your Science Book to pages F14 and F15 Read “What is Energy?” Read the chart on page F15 What types of energy are mentioned on p. F15

Law of Conservation of Energy The law of conservation of energy is a law of science that states that energy cannot be created or destroyed, but only changed from one form into another or transferred from one object to another. 

Types of Energy CHEMICAL ELECTRICAL LIGHT MECHANICAL (Motion) THERMAL (Heat) NUCLEAR SOUND (Acoustic)

Chemical Energy CHEMICAL ENERGY is energy that is stored in a substance’s molecules. Chemical energy is released through a chemical reaction.

Examples of Chemical Energy The energy stored in the food we eat The chemicals that make up an electrical cell or battery The energy that is stored in a fuel such as gasoline, oil, coal. Gasoline and Oil are Petroleum Products

Electrical Energy An atom is made up of three particles: Protons have a positive charge. Electrons have a negative charge. Neutrons have a neutral charge. ELECTRICAL ENERGY is released through the flow of electrons. A generator is used to produce alternating current. A cell or battery releases direct current.

Electrical Energy Electricity Direct Current Alternating Current Static Electricity

Mechanical Energy MECHANICAL ENERGY is energy of motion. Examples Moving Windmill Car Engine The motion of a watch or clock.

Thermal Energy Commonly referred to as HEAT. It is caused by the motion of molecules. The faster molecules move, the more heat or thermal energy an object has. As an object is heated, the movement of the molecules that make it up speed up or accelerate.

Thermal Energy Caused by the motion of molecules The faster the movement of moleculesthe more thermal energyHEAT

Nuclear Energy Caused by the splitting of atoms A huge amount of energy is released Powers the sun Used by Nuclear Power Plants Nuclear Energy  Thermal Energy  Creates Steam  Turns Turbines (Mechanical Energy)  Generates Electricity

Conversion of Energy in a Microwave Oven A microwave oven converts electrical energy into high frequency radio waves that cause the molecules of the food to accelerate or speed up, creating thermal energy or heat.

Key Terms Kinetic Energy—energy of motion A moving car A ball rolling across the floor A windmill moving Potential Energy—energy at rest or stored energy A rock on top of a hill A coiled spring A stretched rubber band

Law of Conservation of Energy The law of conservation of energy is a law of science that states that energy cannot be created or destroyed, but only changed from one form into another or transferred from one object to another. 

Law of Conservation of Energy Energy is transferred from the cue stick to the cue ball. When the cue ball hits the second ball, energy is transferred from the cue ball to the second ball, causing the cue ball to lose energy and to stop, and causing the second ball to move forward. As this second ball collides with the third ball, energy is transferred causing the third ball to travel into the side pocket.

Law of Conservation of Energy The Law of Conservation of Energy can also be demonstrated using Newton’s Cradle.

Transfer of Energy in a Light Bulb In a light bulb, electrical energy passes through the filament. Since the filament, which is made of the mineral tungsten, acts as a resistor, resisting the flow of electricity, electrical energy is transferred to heat or thermal energy. As the filament gets hot, it begins to glow producing light energy. Electrical Energy Filament in Light Bulb Thermal (Heat) Energy Light Energy

Examples of Conversion of Energy EXIT QUIZ A cell converts _________________ energy to ________________. A light bulb converts _______________ energy to ______________ and ______________ energy A car engine converts _______________ energy to _____________ energy.

Examples of Conversion of Energy EXIT QUIZ A generator converts _________________ energy to ________________ energy. A microphone converts _________________ energy to _________________ energy A speaker converts ___________________ energy to ________________ energy.

chemical electrical electrical light thermal chemical mechanical CHECK YOUR WORK chemical A cell converts _________________ energy to ________________ energy . A light bulb converts _______________ energy to ______________ and ______________ energy A car engine converts _______________ energy to _____________________ energy. electrical electrical light thermal chemical mechanical

mechanical electrical sound electrical electrical sound CHECK YOUR WORK mechanical A generator converts _________________ energy to ________________ energy. A microphone converts _________________ energy to _________________ energy A speaker converts ___________________ energy to ________________ energy. electrical sound electrical electrical sound