File:Translational motion.gif

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Summary

Translational motions—the randomized thermal vibrations of fundamental particles such as atoms and molecules—gives a substance its “kinetic temperature.” Here, the size of helium atoms relative to their spacing is shown to scale under 1950 atmospheres of pressure. These room-temperature atoms have a certain, average speed (slowed down here two trillion fold). At any given instant however, a particular helium atom may be moving much faster than average while another may be nearly motionless. The rebound kinetics of elastic collisions are accurately modeled here. If the velocities over time are plotted on a histogram, a Maxwell-Boltzmann distribution curve will be generated. Five atoms are colored red to facilitate following their motions.

Note that whereas the relative size, spacing, and scaled velocity of the atoms shown here accurately represent room-temperature helium atoms at a pressure of 1950 atmospheres, this is a two-dimensional scientific model; the atoms of gases in the real world aren’t constrained to moving in two dimensions in windows precisely one atom thick. If reality worked like this animation, there would be zero pressure on the two faces of the box bounding the Z-axis. The value of 1950 atmospheres is that which would be achieved if room-temperature helium atoms had the same inter-atomic separation in 3-D as they have in this 2-D animation. (L)

Licensing

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Greg L at the English language Wikipedia, the copyright holder of this work, hereby publishes it under the following license: Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled GNU Free Documentation License. http://www.gnu.org/copyleft/fdl.htmlGFDLGNU Free Documentation Licensetruetrue This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Attribution: Greg L at the English language Wikipedia You are free: to share – to copy, distribute and transmit the work to remix – to adapt the work Under the following conditions: attribution – You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work). share alike – If you alter, transform, or build upon this work, you may distribute the resulting work only under the same or similar license to this one. This licensing tag was added to this file as part of the GFDL licensing update.http://creativecommons.org/licenses/by-sa/3.0/CC-BY-SA-3.0Creative Commons Attribution-Share Alike 3.0 truetrue

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• Temperature
• Thermodynamic temperature