Diffusion Model through Conservation of Momentum and Energy

This is a sequence of activities that build up a simulation of diffusion in VPython from basic principles of elastic collisions - ideas of conservation of momentum and energy. The sequence begins with students modeling two particles colliding, moves to confining many particles in a box, and ends with an activity designed to simulate proteins diffusing in water. Learning goals include representing conservation of momentum between 2 colliding particles, parsing long Python code into chunks that identify elements to be changed, and modifying Python code to incorporate conservation of momentum and kinetic energy in elastic collisions.

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