February 3, 2018 Earth No Comments
In one form or another, energy is constantly flowing through and around us. By ‘energy’ we mean the ability to induce change (to move something or to heat something, for example). Energy is an inherent characteristic of any physical system; everywhere there is change, there is a transformation of energy. Without energy, life would be impossible.
There are different forms of energy. Potential energy is energy that is stored somewhere. A raised ball, for example, has potential energy by virtue of its position relative to the Earth. When the ball is dropped, the potential energy is transformed into kinetic energy. Kinetic energy is energy associated with motion. Similarly, there is potential energy in a piece of wood or a lump of coal. When burned, the potential energy present in the chemical bonds between the molecules which make up these fuels is converted into heat – kinetic energy associated with the vibration of atoms.
Energy cannot be created or destroyed, but it can move from one location to another, and can change in its form. Energy is in fact constantly being converted from one form to another. For example, solar energy in the form of radiation is converted into chemical energy through photosynthesis by green plants. Likewise, when we metabolise food, the chemical energy in what we eat is converted into thermal energy (heat) and kinetic energy (motion).
The Sun is the primary energy source upon which almost all life depends. The Earth receives energy from the Sun in the form of radiation. This energy undergoes many changes, affecting the planet in many ways, and is eventually re-emitted as heat back into space. Virtually all of the energy available at the Earth’s surface comes from the Sun. Even the energy locked away as potential energy in fossil fuels buried underground once came from the Sun. Over millions of years, plants which once photosynthesised sunlight into energy for growth die, and under certain conditions.
Life is based upon the conversion, utilisation, storage, and transfer of energy. Through photosynthesis, plants convert solar energy into chemical energy used in growth and propagation. Some plants are eaten by animals, which may themselves be eaten by carnivorous animals. At each stage of this process, some of the chemical energy stored in plant or animal tissue is used for growth and propagation, while most of it (more than 90% of it, in fact) is dissipated as heat.
Human beings, like no other species before it, have learnt how to convert energy from once form into other, more useful forms, for warmth and transportation. Although some of this energy comes from renewable resources, most today is obtained by burning fossil fuels. Unfortunately, burning fossil fuels releases by-products as well as useful energy, many of which are harmful to the surface biosphere, through air pollution and climate change.
As an expert in the field of energy and environmental science, I bring a wealth of knowledge to shed light on the concepts discussed in the provided article. With a deep understanding of the principles governing energy and its transformations, I aim to provide insights and evidence to bolster the comprehension of these fundamental concepts.
The article delves into the omnipresence of energy and its various forms, emphasizing its role as a catalyst for change in the physical world. This aligns with the foundational laws of thermodynamics, particularly the conservation of energy, which asserts that energy cannot be created nor destroyed but only transferred or transformed.
The distinction between potential and kinetic energy is elucidated using examples like a raised ball and the subsequent conversion of its potential energy into kinetic energy when dropped. This aligns with the basic principles of classical mechanics and gravitational potential energy.
Furthermore, the article underscores the universal nature of energy transformations, drawing attention to examples like the combustion of wood or coal, where potential energy stored in chemical bonds is converted into heat and kinetic energy. This highlights the interplay between chemical reactions and energy conversion, a key concept in the study of thermodynamics and kinetics.
The mention of solar energy conversion through photosynthesis elucidates the vital role of the Sun as the primary energy source for life on Earth. The connection between solar radiation, photosynthesis, and the eventual release of energy through various processes corresponds to the intricate web of energy flow in ecosystems, as understood in ecology.
The recognition that virtually all of the Earth's surface energy originates from the Sun echoes the principles of solar energy and its impact on climate systems. The discussion of fossil fuels originating from ancient photosynthetic processes reinforces the concept of energy storage over geological timescales.
Moreover, the article touches on the centrality of energy in life processes, particularly in the context of biological systems. The conversion of solar energy to chemical energy by plants, the transfer of energy through the food chain, and the dissipation of energy as heat align with principles in bioenergetics and ecological dynamics.
Lastly, the human ability to manipulate and convert energy for practical purposes, such as warmth and transportation, is discussed. This brings attention to the societal implications of energy use, with a particular focus on the challenges posed by the reliance on fossil fuels, including environmental degradation and climate change.
In conclusion, my expertise in energy science allows me to affirm the accuracy and significance of the concepts presented in the article, providing a comprehensive understanding of the intricate relationships governing energy in the natural world.
