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Name:  Venkatesh K.
Status: student
Age: 20s
Location: N/A
Country: N/A
Date: 2000-2001


Question:
Why is it that only a sinewave can preserve its shape when it passes through a circuit while no other waveform can?


Replies:
Venkatesh,

A standard circuit has some parts that depend on the current, some that depend on the rate at which the current changes, and some that depend on the total effect of the current over time. The rate of change is the slope of the current. The slope of a sine wave is a cosine wave, which is the same shape as a cosine wave. The total effect of the current over time is the area under the current function. For a sine wave, this works out to be the opposite of a cosine wave. If you add together sine and cosine waves that have the same frequency, you get a sine wave shifted to the left or right. A sine wave is the only function to have these properties without getting steadily larger or steadily smaller.

Dr. Ken Mellendorf
Illinois Central College



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