Energy: its forms and uses What is energy? Energy is defined as; the ability to do work or cause a change. Energy occurs in many forms and is used in our everyday lives. It can be observed in cycles, patterns, and systems. What would our world be like without energy? We would not be able to do work or cause change. What does energy look like? Energy takes many forms, such as; mechanical, light, electrical, sound, and thermal. How is each form of energy used? Energy is used to power our homes and cars. It is also used to power our bodies. Basically, it is used to do work! Why does energy in circuits require a complete path to flow? Without a complete path, electrical energy would not flow to power a light bulb or a doorbell. What are alternative energy sources? Alternative energy sources are solar, wind, and water. These forms of energy are cleaner forms that don’t produce a pollution byproduct. Energy can be neither created nor destroyed, just like matter, because matter and energy are the same!

Mechanical Energy …is energy stored in objects by tension. A stretched rubber band is an example of stored mechanical energy. Once you let the rubber band go, it has energy in motion. To better understand this, you need to know about POTENTIAL and KINETIC energy. All forms of energy can be divided into these two categories. Potential energy is stored energy and the energy of position — gravitational energy. There are several forms of potential energy. For example; If I have a book sitting on a desk, it has potential energy while laying there. If I push the book off the desk, it is now in motion due to gravity and has kinetic (energy in motion) energy. Kinetic energy is motion — of waves, molecules, objects, and substances. A bicycle is an example of mechanical energy too. When not being used, it has stored or potential energy (mechanical). When you get on it and pedal, it has energy in motion (kinetic energy).

Light Energy Light is a type of radiant energy (radiation). We see use it in our classrooms, while using flashlights, and lamps. This type of light is “visible” light. Sunshine is radiant energy, which provides the fuel and warmth that make life on Earth possible.

Sound Energy …is the movement of energy through substances. Sound is produced when a force causes an object or substance to vibrate — the energy is transferred through the substance in a wave. Typically, the energy in sound is far less than other forms of energy.

Electrical Energy …is what is stored in a battery, and can be used to power a cell phone or start a car. Electrical energy is delivered by tiny charged particles called electrons, typically moving through a wire. Lightning is an example of electrical energy in nature, so powerful that it is not confined to a wire.

Thermal Energy Energy from heat: The most abundant form is energy from the sun.

Convection Air near a hot object gets hot and takes up more space. Because the hot air is less dense, it is forced up by the cooler, denser air around it.

Conduction Thermal energy moves from an electric stove burner to a metal pot by Conduction Conduction happens every time you grab something hot or cold.

Motion Energy …is energy stored in the movement of objects. The faster they move, the more energy is stored. It takes energy to get an object moving and energy is released when an object slows down. Wind is an example of motion energy.

Chemical Energy …is energy stored in the bonds of atoms and molecules. Biomass, petroleum, natural gas, and coal are examples of stored chemical energy. Chemical energy is converted to thermal energy when we burn wood in a fireplace or burn gasoline in a car's engine.

Nuclear Energy …is energy stored in the nucleus of an atom — the energy that holds the nucleus together. Very large amounts of energy can be released when the nuclei are combined or split apart. Nuclear power plants split the nuclei of uranium atoms in a process called fission. The sun combines the nuclei of hydrogen atoms in a process called fusion

Fuel Any material that can burn Such as; coal, wood, oil, And gas.

Alternative Energy Forms Solar Energy – energy given off by the sun Wind energy – energy caused by The movement of air Water or hydroelectric energy- Movement of water turns turbines to create electricity