MHB Complex wave forms and fundamentals.... Very very stuck

AI Thread Summary
The discussion revolves around tackling a complex waveform problem involving a combination of sine functions. The user seeks guidance on determining the amplitude and frequency of the fundamental, as well as the harmonic components' order, amplitude, and phase angles. A response suggests starting with the definitions provided in course materials and emphasizes understanding the periods of each sine term, noting that the overall period is determined by the largest period among them. The key takeaway is to analyze the individual sine components to derive the necessary characteristics of the waveform. Understanding these fundamentals is crucial for solving the complex waveform question effectively.
JPorkins
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Hi,

My teacher tasked me with a complex waveform question, i have looked for some time to find out how to tackle these, but i still do not know where to begin.
Any help would be greatly appreciated, not look for an answer just a method.

$$i=12sin(40*\pi t) + 4sin(120* \pi t - /3\pi) + 2sin(200 \pi t + /2\pi)$$
determine the
amplitude of the fundamental
the frequency of the fundamental
The order of harmonic components
amplitude of harmonic components
the phase angle of harmonic components

Thanks,
Jack
 
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JPorkins said:
Hi,

My teacher tasked me with a complex waveform question, i have looked for some time to find out how to tackle these, but i still do not know where to begin.
Any help would be greatly appreciated, not look for an answer just a method.

$$i=12sin(40*\pi t) + 4sin(120* \pi t - /3\pi) + 2sin(200 \pi t + /2\pi)$$
determine the
amplitude of the fundamental
the frequency of the fundamental
The order of harmonic components
amplitude of harmonic components
the phase angle of harmonic components

Thanks,
Jack

Hi Jack,

Which definitions does your course material give for those?
And what does your course material say on how to find them?

As a starting point, $\sin(t)$ has a period of $2\pi$, so that $\sin(k t)$ has a period of $\frac{2\pi}{k}$.
Which periods do the respective sine terms have?
Note that if one is a multiple of another, their sum has a period that is equal to the largest one.
 
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