In physics, energy (from the Greek ἐνέργεια - energeia, "activity, operation", from ἐνεργός - energos, "active, working"[1]) is a scalar physical quantity that describes the amount of work that can be performed by a force, an attribute of objects and systems that is subject to a conservation law. Different forms of energy include kinetic, potential, thermal, gravitational, sound, light, elastic, and electromagnetic energy. The forms of energy are often named after a related force.
Any form of energy can be transformed into another form, but the total energy always remains the same. This principle, the conservation of energy, was first postulated in the early 19th century, and applies to any isolated system. According to Noether's theorem, the conservation of energy is a consequence of the fact that the laws of physics do not change over time.[2]
Although the total energy of a system does not change with time, its value may depend on the frame of reference. For example, a seated passenger in a moving airplane has zero kinetic energy relative to the airplane, but non-zero kinetic energy relative to the Earth.
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Jeff Chidester
Wed, 29 Jul 2009 14:30:00 GM
Advice To The Birthers: Focus Your . Energies. Elsewhere. I have tried to stay out of the "birth certificate" controversy because it is a non-issue. Lee Harvey Oswald killed JFK, man landed on the moon, Jimmy Hoffa was killed by the mob, ...
Q. The question asks: For each element, predict where the "jump" occurs for successive ionization energies. For example, does the jump occur between the first and second ionization energies, the second and third, or the third and fourth? The book gives a few examples of elements and provides the answers, but I do not understand how it gets the answers. For Be, it says the jump occurs between the 2nd and 3rd. For O it says between the 6th and 7th. For N it says between the 5th and 6th, and so on. What do I have to do or know in order come to these conclusions? Thanks in advance.
Asked by charlie - Mon Nov 17 16:54:40 2008 - - 2 Answers - 0 Comments
A. hey charlie!! Gosh your teachers are tough!! Ok so ionization energies...the best way to predict them is to have your periodic table infront of you and know how to write electronic configurations. Just going to give you some knowledge first on the periodic table and ionization energies...if you look at your table and see lithium,sodium,potassium. ..etc the last element at the bottom is Fr right?? so if you look at the bottom of the periodic table and draw an arrow up...the ionization energies increase ...so Cs will have a greater number than Fr, Rb will have a greater number that Cs...K will have a greater number than Rb...and so on...so ionisation energies increase from botton to top in thier colomns...ok then if you look at your… [cont.]
Answered by creole237 - Mon Nov 17 18:55:40 2008
