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Subject: Re: Old easy question?

Date: 01/30/02 at 9:41 AM
Posted by: Mike
E-mail: vklacar@sprint.ca
Message Posted:

In Reply to: Re: Old easy question? posted by tom on 01/28/02 at 1:17 PM:

Thank you all for your follow ups. You have answered ALMOST all of my questions. However I guess I am asking a more of physics type of question, meanwhile you all gave me the classic text book type response. What I am really asking is this. I know that ac alternates between positive and negative cycles. Now Tom you said in the negative cycle that the "hot" wire is negative with respect to ground. In Ac distribution the ground is the "neutral" white wire which is all physically connected to the earth. Now during the negative cycle, the ground is positive with respect to the hot wire, THAT means that earth ground actually acts like the positive supply and it has to push out electrons. Right? Now I am asking is how it does this?, I always thought of earth ground as a huge plane where electrons flow into, NOT out of.

Another side question I always wondered, if current is cycling at a frequency of 60 Hz, is there some limitation to the actual length of the transmission wire. Here is what I mean: one positive cycle last 1/60 = 0.0167 seconds. Now let's assume that electrons travel at the speed of light, I don't think they travel that fast, but let's say for arguments sake they do. So in the metric system the speed of light = 300,000km/s. You take the time for the positive cycle and you 300,000km/s*0.0167 = 5000 km. So is right to say that you CAN NOT have a distribution line longer then 5000 km because the current would not reach the load BEFORE the cycle changes. This question might be trivial because there may be many other factors which inhibit current flow to a certain length that I am not aware of. Thank you all for your comments. Regards.

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