After the engine starts chemical energy in the fuel

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energy. After the engine starts, chemical energy in the fuel is converted to kinetic energy (and heat) by the engine. Energy transformations are subject to two fundamental rules with profound consequences for the ecosphere. These rules are called the Laws of Thermodynamics. First law of Thermodynamics:
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So, in a closed system (no energy in or out), total energy is a constant. Earth isn’t a closed system, but the sun is almost our only source of energy. So, we must make do with whatever energy we receive from the sun plus whatever is already stored in the ecosphere. Second law of thermodynamics: Energy quality: an intuitive description of how easily useful work can be from a given source of energy. \ Usually, the least useful form is low-temperature waste heat that is released into the environment. The laws of thermodynamics are unforgiving. First we cannot create energy from nothing. And second, we can’t even break even. The ratio of the remaining useful energy after transformation to the input total energy is called the conservation efficiency. Some efficiencies: Electric generator (say on a bicycle) 99% Oil furnace 65% Cellular respiration (food to energy) 40% Automobile engine 25% Fluorescent lamp 20% Incandescent light bulb 4% Photosynthesis 2-5%
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