During a classroom demonstration, Mr. H uses a wave machine donated to the school by Bell Telephone Company. The wave machine consists of two 1-meter length sections of 50 steel rods. The steel rods are connected to each other so that when the first rod is disturbed from a rest position, the disturbance travels along the medium from rod to rod. One of the sections consists of longer steel rods; disturbances move at 20 cm/s in this section. The other section consists of shorter steel rods; disturbances move at 80 cm/s in this section. Mr. H connects the two sections together so that pulses can cross the boundary from one section to the other. He introduces a pulse with a length of 10 cm into the slower section. Determine the length of this pulse when it crosses the boundary into the faster section.
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Boundary Behavior