0 5 Wave Intro

This video was made for a junior electromagnetics course in electrical engineering at Bucknell University, USA. The video is designed to be used as the out-of-the-classroom component and combined with active learning excercises in class. This video covers the relationship of complex numbers and waves, giving a basic introductions to properties of waves

[@trizarabia]

As simple as it might seem; this content includes some profound change in basic understanding that students should consider every word in the context!

[@altuber99_athlete]

5:28 To avoid that, I prefer to call _ϕ_ as the _phase_ of the sinusoid, and to call _θ_ = _ωt_ + _ϕ_ as the _instantaneous phase_ of the sinusoid.

[@DeadCatX2]

Could also call ϕ the _phase offset_

[@lubime10]

I am looking for the 03 and 04 videos and I did not find them Any help please !

[@kridnix]

0.3: 0 3 scalar algebra 0.4: 0 4 Complex Algebra

[@mdesm2005]

Why do you need a cosine and a sine to represent one sinusoid? Why isn't one sine or one cosine sufficient?

[@kridnix]

This will come out later (3.X videos), but basically wave problems are solved with differential equations, and these are much easier to solve if you use the exponential form. You can of course use sine and cosine through Euler's Rule... So much for the math. A more physical but not exact explanation is to account for the energy of a wave when the amplitude is zero. If you just looked at the real part the instantaneous energy would be zero with zero amplitude. By using a complex notation when the real measured part is zero, all the energy is in the complex part. This doesn't help much, but what it means is when the electric energy is zero, the magnetic energy is max or v.v.- the energy simply shifts forms and the complex sinusoid helps account for both forms. A real physicist would probably rip me a new one for this hand-waving explanation, but that is how I think of it...

[@altuber99_athlete]

One sine/cosine _is_ sufficient. Try that yourself. However, you'll realize it's easier to solve a problem with two sinusoids instead.