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This is Dr. Ferri, and this an extra

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problem for demonstrating how to use the
frequency spectrum.

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I'd like you to be able to recognize
frequency

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content of signal as it's shown in the
frequency spectrum,

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as well as the frequency content of the
signals

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as you see it in the time domain, shown
here.

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So this problem asks you to match the time
domain

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voltage waveform to the appropriate
frequency spectrum on the left.

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So let's start looking at this, let's look
at this one right here, this one has a DC

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value, so this is for DC.
A DC component plus some higher frequency.

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Now the ones on the right, there's only
one of them that has an offset.

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You see this offset of one, is the same as
that value right here.

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So this frequency, this sine wave is
offset by a

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value of one, so this one has to be that
frequency

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spectrum there.

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And then of the other two, if we look at

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them, this one has a low frequency that
kind of dominates.

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And this one, the higher frequency
dominates.

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So, off over on, on this synch, the low

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frequency dominates here and here the high
frequency dominates so,

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they look like this.

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right there and then like that, so this is
how they match up.

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So, just to summarize here, I looked first
at any that had DC components and

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that corresponds to an offset and then

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I really looked at what the frequencies
were.

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Since these two had the same frequencies,
the only difference

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was their amplitudes and in which case,
which one dominated.

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This one, the high frequency would
dominate

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and this one, the low frequency would
dominate.

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Thank you.