how do i show internal movement of particles(sustances) in a documentary..i am doing a physics class lecture project,showing how electricity is transfered around a circuit..i would like a blue line to move around a circuit as the voice over is explaining how the electric concept works..i've seen this technique in several tutoring video.e.g. showing the food going down the digesting system..in another one,i have to show how streess are distributed in a building subjected to loading..How can this be achieved..

having tough time

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