ENERGY

Energy – Definition: Looking around us we see that the plants grow, move animals and machines and tools make the most varied tasks. All these activities have in common that require energy contest. Energy is a property associated with the objects and substances and is reflected in the changes that occur in nature. The energy is manifested in the physical changes, for example, by raising an object, transporting it, distort it or heat it. The energy is also present in the chemical changes, such as burning a piece of wood or the decomposition of water by electrical current. The energy is a quantity whose unit of measure in the SI is the joule (J). Work: The Work is a form of power transmission between the bodies. To do its work is necessary to exert a force on an object and moving it. The work, W, of a force on a body equals the product of the component of force in the direction of motion, Fx, by displacement, s, of the body. W Fx s The work, W, is measured in joules (J).