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<code> GlowScript 2.8 VPython ## Constants R=8.314 # Gas constant N_A=6.02E23 # Avogodro's constant L = 0.1 # Our container is a cube with L=0.1m on each side Ratom = 0.001 # wildly exaggerated size of a gas atom

## Properties of the gas atoms we are working with N_atoms = 500 # change this to have more or fewer atoms n=N_atoms/N_A # number of moles of gas atoms

Molar_mass = 4E-3 # molar mass of helium in kg/mol

T = 300 # temperature in Kelvin

## Create a container for our gas atoms container = box(pos=vec(0,0,0),size=vec(L,L,L), color=color.white, opacity=0.1)

v_avg = sqrt(8*R*T/(pi*Molar_mass)) # average velocity of gas atoms #v_rms = sqrt(3*R*T/(Molar_mass)) # root mean squared velocity of gas atoms Velocity=v_avg

Theoretical_Pressure=n*R*T/(L*L*L*1000) # Calculate the theoretical pressure based on the ideal gas law

## The lines below create a graph for the heigh vs time. Try creating a graph for the velocity and acceleration Grph1 = graph(title='Pressure vs Time', xtitle='Time (s)', ytitle='Pressure (atm)', fast=False,ymin=0, ymax=5*Theoretical_Pressure) #ymin=0, ymax=2*Theoretical_Pressure ExperimentalPressureGraph = gcurve(color=color.red, label='Experimental_Pressure') TheoreticalPressureGraph = gcurve(color=color.blue, label='Theoretical_Pressure')

t=0 # initialize the time variable dt = 2.5E-9 #time-step interval pressure=0 # initialize the pressure tracker pcount=0 # This counter will track when a particle-wall collision adds to the pressure

## The following lines create all the particles ListOfParticles = [] # Empty list of particles for i in range(0,N_atoms):

  newparticle = sphere(pos=vector(L*random()-L/2,L*random()-L/2,L*random()-L/2),radius=Ratom, color=color.green,opacity=0.7, visible = True) #Create a spherical particle at a random postion
  newparticle.velocity = vector(Velocity*sin(pi*random())*cos(2*pi*random()),Velocity*sin(pi*random())*sin(2*pi*random()),Velocity*cos(pi*random())) #Randomize velocity
  newparticle.mass = Molar_mass/N_A #Give the particles the atomic mass of your gas
  ListOfParticles.append(newparticle) #Append the particle to our list of particles

## The following lines simulate random motion and particle-wall collisions while True:

  rate(9999)
  for particle in ListOfParticles:
      particle.pos = particle.pos + particle.velocity*dt #Update position of every particle based on its velocity
      
      #Check for particle-wall collisions in x,y,z. If there are collisions, add some pressure to the total.
      if abs(particle.pos.x) >= L/2:
          particle.velocity.x = - particle.velocity.x 
          pcount+=1 
          pressure+=particle.mass*abs(particle.velocity.x)/(L*L*dt)
      if abs(particle.pos.y) >= L/2:
          particle.velocity.y = - particle.velocity.y  
          pcount+=1 
          pressure+=particle.mass*abs(particle.velocity.y)/(L*L*dt)
      if abs(particle.pos.z) >= L/2:
          particle.velocity.z = - particle.velocity.z 
          pcount+=1 
          pressure+=particle.mass*abs(particle.velocity.z)/(L*L*dt)
  
  #The following lines calculate the experimental pressure measured due to particle-wall collisions
  if pcount>=1:
      Experimental_Pressure=pressure/pcount # Average the total pressure over the number of particle-wall collisions
      Experimental_Pressure=Experimental_Pressure*101325 # Convert from Pa to atm
      ExperimentalPressureGraph.plot(t,Experimental_Pressure) #Graph the experimental pressure
      pressure=0 # Reset the pressure tracker
      pcount=0 # Reset the pressure counter

  TheoreticalPressureGraph.plot(t,Theoretical_Pressure) #Graph theoretical pressure

  t=t+dt

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