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Andrej Gubina
We are surrounded by different forms of energy. While energy takes up many meanings in our vocabulary, we can define it at its core as the ability to live and to move. We use it to walk, run, cycle and work. Our cars, buses, boats, and airplanes need energy to move. It is stored in our food, our bodies, the plants surrounding us, and the soil we walk on. It is the ability of a system to do work by exerting force on another system over some distance. In this process, the energy is transferred from one system to the other, while some energy is simply lost to the surroundings.
Energy comes in different forms
A lot of times we associate the word energy with electricity. While this is not wrong, we should keep in mind that electricity is not the only type of energy powering this world. In nature, we find many forms of energy, for example heat, light, motion, electrical energy, chemical energy, and gravitational energy. These forms fall into two main categories – potential or stored energy, and kinetic or working energy. All energy falls into one or the other, or sometimes even both at the same time. But their state is not fixed. In our day-to-day life, energy is converted from one form to another – motion energy in the water for example transforms to electrical energy in hydro plants, which then lights up the lights in our house.
Do we create energy in the world?
Energy exists, it cannot be created or destroyed. The amount of energy in the universe is constant and it is finite. Therefore, when we produce energy in power plants, we do not make energy, just transform already existing energy from one type or form to another. Likewise, when we use energy, we do not destroy it, just pass it on to other subjects or change its form again.
Energy powers the Earth
Energy does much more than simply move us from one place to another. Our weather and climate are mostly driven by the energy from the sun. The water cycle, which stores many other types of energy here on Earth, is also driven by the sun and its energy. Energy flow through the earth powers all physical processes on it. It plays a pivotal role in inanimate nature as well as in all aspects of animate nature. The sun is the key source of energy for all organisms and their ecosystems. By giving plants, algae, and other producers the energy to make organic matter from carbon dioxide and water, they start the energy flow through ecosystems and their food webs, which we are all a part of.
Food is a fuel that we and other organisms use to live. It is our main source of energy. However, we, as humanity, affect energy flows throughout all ecosystems even more drastically with other activities. We are constantly modifying Earth’s energy balance due to population growth, technology development, and many other factors.