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Thermodynamics And Energy. Thermodynamics is the branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. Thermodynamics is only concerned with large scale observations. What is Thermodynamics?.
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Thermodynamics And Energy
Thermodynamics is the branch of science concerned with the nature of heat and its conversion to mechanical, electric, and chemical energy. • Thermodynamics is only concerned with large scale observations. What is Thermodynamics?
The study of thermodynamics is important because many machines and modern devices change heat into work. (i.e. An automobile engine or turn work into heat or cooling, such as with a refrigerator.) • Understanding how thermodynamics works helps you understand how machines that use thermodynamics work. Why is the study of thermodynamics important?
Energy has many different forms, all of which measure the ability of an object/system to do work on another object/system. • Energy can be measured. The energy unit is called the Joule, pronounced “jool” and written as "J" in scientific formulas. • One joule is the amount of energy or work done, while applying one Newton force to move an object for distance of one meter. Thermodynamics and energy
6 Basic Forms of Energy • Thermal or Heat Energy: • The kind of energy related to or caused by heat. • When thermal energy is applied to a substance, the molecules speed up, which makes the substance get warmer! • Chemical Energy: • Energy derived from a chemical reaction or absorbed in the formation of a chemical compound.
6 Basic Forms of Energy • Electrical Energy • Energy made available by the flow of electric charge. • All matter is made up of atoms (protons, neutrons, and electrons). • When those electrons move among the atoms of matter, a current of electricity is created.
6 Basic Forms of Energy LIGHT: Electromagnetic Energy • This term is used to describe all the different kinds of energies released into space by stars such as our Sun. • Light is also called "electro-magnetic radiation (EMR)". • Electrons are responsible for emission of most EMR because they have low mass, and therefore are easily accelerated/excited.
Light waves make things visible to the human eye, while x-rays can pass through a person and is used to burn an image on film for medical purposes. • EMR travels in waves, which lets us measure the different kind by wavelength or how long the waves are.
6 Basic Forms of Energy • Mechanical: • It is the energy a substance or system has because of its motion. • Machines use mechanical energy to do work. (duh)
Basic Forms of Energy • Nuclear Energy: • The energy stored in the nucleus of an atom — the energy that holds the nucleus together. • Very large amounts of energy can be released when the nuclei are combined or split apart. • Nuclear power plants split the nuclei of uranium atoms in a process called fission.
The Laws of Heat Power • Thermodynamics are the Laws of "Heat Power." • All things in the observable universe are affected by and obey the Laws of Thermodynamics. The Laws of Thermodynamics
1st Law of Thermodynamics • Also known as the “Law of conservation of matter” • It simply states that energy can be neither created nor destroyed – energy is constant. • If you add hot water to a pot of water at room temperature, the temperature of the water increases, but only temporarily. The system then releases some energy and heats the air around the water. Laws of Thermodynamics
Commonly known as the Law of Increased Entropy. While quantity remains the same (1st Law), the quality of energy deteriorates gradually over time. • In other words, no reaction is 100% efficient. Some amount of energy in a reaction is always lost to heat. • "Entropy" is defined as a measure of unusable energy within a closed or isolated system. • http://www.youtube.com/watch?v=C0NBosKaznA 2nd law of Thermodynamics –Entropy
The third law of thermodynamics tells us that all molecular movement stops at a temperature we call absolute zero, or 0 Kelvin (-273oC). • Since temperature is a measure of molecular movement, there can be no temperature lower than absolute zero. • As a system approaches absolute zero, the abstraction of energy becomes more difficult. 3rd Law of Thermodynamics
