Luke Carlson generating latex version of article  about 11 years ago

Commit id: 61022542984e6d18b99728a151135dc3c8c651d3

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\usepackage[utf8]{inputenc}  \fi  \fi  \usepackage{graphicx}  % We will generate all images so they have a width \maxwidth. This means  % that they will get their normal width if they fit onto the page, but  % are scaled down if they would overflow the margins.  \makeatletter  \def\maxwidth{\ifdim\Gin@nat@width>\linewidth\linewidth  \else\Gin@nat@width\fi}  \makeatother  \let\Oldincludegraphics\includegraphics  \renewcommand{\includegraphics}[1]{\Oldincludegraphics[width=\maxwidth]{#1}} \usepackage{url}  \ifxetex  \usepackage[setpagesize=false, % page size defined by xetex  unicode=false, % unicode breaks when used with xetex 

In this lab, I set out to create a 3D simulation of ideal gas particles  in a cubic container in order to experimentally determine the pressure  of the gas based on given circumstances, such as circumstances. From there, I planned to  explore  the the volume of the  container relationship between pressure  and the temperature of the system. volume.  To produce an accurate simulation, a replication of a real world  circumstance using programming, of a gas particle it is first necessary 

written as $Pressure=F/A$. Force can also be described as change in  momentum over change in time: $F = \frac{\Delta p}{\Delta t}$. The  change momentum of a single particle equals its mass multiplied by its  change in velocity: ${\Delta p} = m\Delta v$ v$.  Since there is more than one particle in a system, the entire change in momentum is the combined  change in velocities of each particle that hits the specified area.  Thus, the following formula can be used to determine total force:  ~  $F = \frac{2m * \displaystyle\sum\limits_{0}^n v}{\Delta t}$ Where $n$ is the number of collisions and $v$ is the velocity of the  particle hitting the wall. Since the change in velocity is double the 

Once the force has been computed using the momentum of the particles,  the pressure can then be determined with the initial formula $P = F/A$.  \begin{figure}[htbp]  \centering  \includegraphics{figures/Screen Shot 2013-01-19 at 6.37.29 PM/Screen Shot 2013-01-19 at 6.37.29 PM.png}  \caption{image}  \end{figure}  \section{Hypothesis}  Increasing the number of particles in the simulation will yield a  pressure closer to the actual value (determined using the Ideal Gas  Law). Furthermore, increasing the volume of a container will decrease  the pressure in the system.  \section{Method}  \subsection{Computing Pressure}  I started began constructing my simulation with '3D Balls Bouncing', a project  from Open Processing, as a base. Starting  off with a system that could  already handle 3D collisions of small objects inside a container was  necessary {[}see Failed Methods{]}. From there, I created small spheres  with the properties of an ideal gas. Their speed was roughly determined  on a Maxwell-Boltzman distribution and assuming that the most probable  speed ($V_{p}$) would occur the most often (calculated using the formula  $V_{p} = \sqrt{\frac{2kT}{m}}$. Next, I focused on one wall in the  container and tracked each time a particle collided with the area. I  could then compute the change in momentum over the area since I had the  masses and velocities of the particles. The simulation did not keep  track of total time since initiation, which is equivalent to time, but I  knew that aspects of the code were executed every frame. The project ran  at a fixed number of frames per second (60) so I designed this formula  to figured out the change in time:  $total\ time (seconds) = \frac{total\ frames}{frames\ per\ second}$.  I inserted that data into this formula  $F = \frac{2m * \displaystyle\sum\limits_{0}^n v}{\Delta t}$ (see  Introduction) to find the total force on the wall. To obtain the  pressure, I just divided the answer  by creating the area of the wall.  \subsection{Testing Accuracy}  Now that I was able to compute the pressure, I could test my hypothesis  by increasing the number of particles in the system and comparing the  pressure readings. I started off with 5 particles and then tried 10, 15,  and 20 particles. I calculated the total pressure of each system once  every 5 seconds for 20 seconds.  \subsection{Experimentally Assessing the Relationship Between Pressure  and Volume}  The next step of  my own experiment involved manipulating the volume of the  container while keeping the number of particles constant. In order to do  so, I altered one line of code in the box Class:  \texttt{int boxsize = 300;}  This variable alters the dimensions of the box (currently 300x300x300  pixels). I changed the boxsize to 400, 500, and 600, and calculated the  pressure every 5 seconds for 20 seconds.  Since the simulation could not handle a large number of particles, I  \section{Attempted \subsection{Failed  Methods} I originally designed my own 3D collision system but it was less  efficient so a computer could not render as many particles in the 

Concisely state the results and what I learned  \begin{figure}[htbp]  \centering  \includegraphics{figures/figure_1/friedrich-wanderer-above-the-sea-of-fog-1200x1024.jpeg}  \caption{image}  \end{figure} \section{Improvements}  \begin{enumerate}  \item  Since the simulation could not handle a large number of particles, I  had to resort to using an unrealistically low number of particles  (e.g. 5 particles vs $5 x 10^{23}$).  \begin{enumerate}  \item  This also meant that my Maxwell--Boltzmann distribution would not be  as precise because if a particle obtained a truely outlier speed, it  would greatly affect the results  \end{enumerate}  \item  Add more improvements \ldots{}  \end{enumerate}  \section{Bibliography}  \begin{itemize}  \item  "Maxwell Speed Distribution Directly from Boltzmann Distribution."  Development of Maxwell Distribution. N.p., n.d. Web. 07 Mar.  2013.\textless{}\url{http://hyperphysics.phy-astr.gsu.edu/%E2%80%8Chbase/kinetic/maxspe.html}\textgreater{}.  \item  "Language Reference (API) Processing 2." Language Reference (API)  Processing 2. N.p., n.d. Web. 07 Mar. 2013.  \textless{}\url{http://processing.org/reference}\textgreater{}.  \item  "3D Balls Bouncing- OpenProcessing." 3D Balls Bouncing-  OpenProcessing. N.p., n.d. Web. 07 Mar. 2013.  \textless{}\url{http://www.openprocessing.org/sketch/20136}\textgreater{}.  \item  "Kinetic Theory." Wikipedia. Wikimedia Foundation, 03 Apr. 2013. Web.  07 Mar. 2013.  \item  "The Distribution of Molecular Speeds." ChemEd. University of  Wisconsin, n.d. Web. 10 Mar. 2013.  \textless{}\url{http://chemed.chem.wisc.edu/chempaths/GenChem-Textbook/Kinetic-Theory-of-Gases-The-Distribution-of-Molecular-Speeds-941.html}\textgreater{}.  \item  "Including Graphics in a LaTeX Document." Including Graphics in a  LaTeX Document. University Of Colorado Boulder, n.d. Web. 10 Mar.  2013.  \textless{}\url{http://amath.colorado.edu/documentation/LaTeX/reference/figures.html}\textgreater{}.  \end{itemize}  \end{document}