An alternative for teaching and learning the simple diffusion process using Algodoo animations

Abstract

In this work, animations of the random walk movement using a freeware Algodoo software were done in order to support the teaching of the concepts of Brownian motion. The random walk movement was simulated considering the elastic collision between the particles in suspension in a fluid. The intensity of the particles’ velocities in our simulation were defined in an arbitrary range, and a random distribution of the velocity directions. Using two methods, the distribution histogram of displacements and the mean-square-displacement, it was possible to measure the diffusion coefficient of four different simulated systems, and determine the regions where the system presents ballistic regime or diffusive transport regime. The ballistic regime was observed graphically when the mean-square-displacement has a parabolic dependence with time, which differing from the typical diffusive regime where mean-square-displacement has a linear dependence. The pedagogy strategy is to blend the mathematical description of Brownian motion using animations with Algodoo, supporting the teaching and learning processes.