In Ancient Greece, several centuries before Christ, energeia meant “working” or “in action”. French and English have kept this sense of the word. Energy is force in action everyday!
- Kicking a football gives rise to a movement of the ball in the direction of a teammate or the opponent’s goal. The force of the pass, or the shot, imparts energy to the ball.
- The flame of a gas cooker provides the energy necessary for the water to cook the pasta.
- The energy produced by the jet engines of a plane means that it will fly and not crash to the ground.
- The energy from a waterfall allows us to make electricity.
- Light energy from the sun is responsible for the growth of plants.
From the above, a first simple definition can be deduced: energy represents the ability to produce action. For example, it can give rise to movement, it can change the temperature of a body or it can transform matter. Energy comes from different sources that can be found naturally: wood, coal, gas, wind, sunlight, moving water and uranium. It can take different forms, for example: heat energy, muscular energy, mechanical energy, chemical energy and electrical energy. And energy is capable of being transformed from one to another of its many forms.
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