Energy
Anywhere in the Universe… You may observe that living things need to “do things” (move, live, perform work) You may observe that non-living things can move, change, or perform work. You may observe that living and non- living things can interact and make other things “happen” or perform work.
What do we mean by “doing things” like performing work? Examples in Living Things: Walking, jumping, running, swimming, moving, falling Eating, digesting food, breathing, drinking Growing, changing, developing Examples in Non-Living Things: Falling, bouncing, recoiling, stretching, moving Making sound Releasing heat (“being hot”) Conducting an electric current or containing an electric charge Reacting (going through a chemical reaction or causing a chemical reaction) Notice that many of the items on these lists can be on the living or non-living list. Remember that living things are made of non-living things. What do we mean by that?
What does it mean to be able to “do things” or perform work What does it mean to be able to “do things” or perform work? What does a living or non-living thing have to possess or have? It must possess…
Energy
Facts you must know about energy: Energy cannot be created or destroyed (Law of Conservation of Energy). Energy can change forms (or types). There are two basic kinds of energy: Potential and Kinetic. Extra for you ambitious young scientists, Einstein’s Formula: E = mc2 (Energy equals mass times the speed of light squared)
Potential Energy: Energy that is stored or has the ability to start moving Kinetic Energy: Energy that is in motion
What are some types of potential and kinetic energy?
Energy’s Forms: Potential Energy Gravitational Energy Energy stored in an object that gets more powerful as it goes higher. Chemical Energy Stored inside chemicals such as food and batteries, that can be used later. Nuclear Energy Energy produced when atoms break apart or fuse together. Mechanical Energy Such as energy stored in springs that can be released when relaxed.
Energy’s Forms: Kinetic Energy Motion Energy Energy in a moving object, such as wind. Thermal Energy Energy released as heat. Sound Energy Energy waves that we sense with our ears. Light Energy Energy found in light. Electric Energy Energy passed through an electric current.
Energy Changing Forms: Examples Chemical Energy to Electrical Energy Chemical energy in a battery can change into electrical energy that travels through a wire. Electrical Energy to Light and Thermal Energy Electrical energy traveling through a light bulb will emit light energy and thermal (heat) energy. Wind Energy to Electrical Energy Wind turbines capture the motion energy of wind and convert it to electrical energy using a generator. Solar (Light) Energy to Chemical Energy Plants use solar energy to produce chemical energy inside of sugar. This is called photosynthesis. Gravitational Energy to Motion Energy A car can gain motion energy by traveling downhill and picking up speed Motion Energy to Sound Energy When two objects collide, they can release sound energy through the air through sound waves.