Free Particle Exercise #2

Please answer the  following 3 questions regarding the Physlet:


Wave Functions Probability Densities Probability Density


The animation shows the time development of a free particle (Gaussian wave packet).  The graph shows the real (red) and imaginary (green) parts of the wave function, the real (red) and imaginary (green) contributions to the probability density and the total probability density.  At x = 10 and x = -10 the particle experiences the hard walls of the simulation, otherwise it is free.


Watch each animation for 2 time units before answering the following questions.

  1. At t = 0 and t = 1 what is the probability of finding the particle between x = -10 and x = 10? 
  2. How does the maximum amplitude and width of the wave packet change with time?
  3. Explain your answer to question 2.  Try to be as complete as possible.


Script by Mario Belloni and Wolfgang Christian.
Questions by Mario Belloni.
Java applets by Wolfgang Christian.