Can someone explain how this electrical barrier affects some living creatures but not all?
There is an electrical barrier to stop carp from coming through to the great lakes:
You don’t need to watch the video as it doesn’t answer my question, but here
small fish are fine, birds are fine, but carp get shocked and just knocked out. Humans would probably die of cardiac arrest.
If it’s the same current per second or whatever, how are small fish not affected but big fish are? How is there a “greater that 50% chance” that a human would die if birds are just fine (and small fish lol).
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I know how this works.
I am going to make some broad statements so you get the general idea and get what I’m saying. Every point can be argued but that is small stuff. You need to understand 3 basic concepts.
Concept #1: It is the difference in voltage across your body that kills you. If you have 1 volt leads attached to both arms and your legs are somehow insulated and not touching the ground, nothing happens. If you bump the voltage up to 10 volts, 100 volts etc. Nothing happens. BUT if one arm lets go and touches ground, Poof! You’re toast, because now you have one arm at 0 volts and the other at 100V – a difference.
See that?
Concept #2: Water is in the ocean or lake is at zero volts or “ground”. .That is why you get fried if you hold an electrical wire in one hand and step in the water.
Concept #3: A high voltage wire in water has an electrical field around it that drops off with the distance from the wire. If you are very close to the wire you will see high voltage. If you are far away, you see no voltage or “ground”. This field drops off quickly with distance from the high voltage. Depending upon the water, and dissolved minerals you can measure 10,000 volts at the wire, but only a small voltage 3 feet away. (There are tables and simulations to figure this out.) If you are a foot away you might only measure 1 volt. If you are 6 inches away you might measure 100 volts. If I recall this voltage versus distance is a cubic relationship.
Now imagine you are a tiny fish swimming in the water. Your nose is always at the same voltage as your tail because they are at the same distance from the source voltage.
Now imagine you are a long fish, 3 ft long, As you get near the wires your nose is at a higher voltage than your tail. You feel the voltage stating to go through you so you pull away and avoid the high voltage. If you were foolish enough to get really close you’d be cooked, but you pull back because it hurts. The small fish pass right by because they don’t feel anything because their fronts and backs are close together.
The Dept of Env Conservation has studied the fish and know what voltage they need to discriminate between good and bad fish. They also know the best time to do this so the target fish are of a greater size than the good fish.
Humans, being large, would be toast.
I hope this helps.
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