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Aiee!

Sorry...

Impulse Graph The correct solution in this case is the impulse function, since the gasoline all enters the reservoir at once.



Why not a step function?

Step Graph The step function does not represent this situation very well. Remember that a step input function is used to represent input that starts and then continues steadily over a period of time. Here, once the tank falls into the reservoir, the gasoline enters the lake nearly instantly. There is no further input of contaminant after the initial surge. An example of a step function is the earlier question about the electroplating company which starts operation and begins sending a relatively constant amount of nickel into a nearby stream.

You may want to review the differences between the types of input functions now before you go on. Try coming up with your own examples of both step input functions and impulse input functions.

Go on ->


John Hoggard <hoggard@math.vt.edu>
Last modified: Sun Aug 10 17:43:06 EDT 1997