So you think wire conductors in cables are directional? Think again...

andy21,290 posts05-13-2021 5:24pm

It's just not true...especially for AC. The AC current travels in both directions. Here's an easy explanation.

Wrong. AC current travels in one direction. Look up Poynting vector. We've been through this. You're a bit late to the party.

The link you provided is like high-school level for those who can't get past first year college.

Watch this animation. The vector moves in one direction. The current does not...hence Alternating Current. Like turning the pedals on a bicycle.


https://brilliant.org/wiki/poynting-vector/

andy21,290 posts05-13-2021 5:24pm

It’s just not true...especially for AC. The AC current travels in both directions. Here’s an easy explanation.

Wrong. AC current travels in one direction. Look up Poynting vector. We’ve been through this. You’re a bit late to the party.

The link you provided is like high-school level for those who can’t get past first year college.

You’re also convoluting the discussion of which direction the current should flow through the conductor...which is also not true. It’s the purity that matters more than the direction it was drawn...which is zero.

Reverse the leads at the speaker and the drivers change direction based on the polarity of the charged magnets. The AC pulses back and forth. 

@andy2 Legit curious question: What more than 1's and 0's constitutes digital signal?

Legit curious question: What more than 1's and 0's constitutes digital signal?

1's and 0's are the abstraction.  There is really no 1 and 0 in real world data.  It's just the voltage level.  We assign a high voltage as 1, and low voltage as 0, but that voltage level can be anything.  You can also call high voltage as 0 and vice versa if you want.  There are rise time fall time.  There are jitter.  There are overshoot, undershoot.  It's all analog.

What most don't see is how these can affect the signal jitter.  Why does jitter matter in audio?  Because the DAC needs a clock and if the clock is affected by jitter, the audio coming out will be affected too.

Most RF engineers probably don't get it.  I know because I get asked this same question by a lot of so called "electrical engineer", and I have to explain this to them.  They would soon understand.