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Name: Ward
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Is there a simple way to describe the difference between current density and charge density? I have been told that when stimulating a nerve, the charge density is more important.

Charge density is the net amount of charge within a volume: How many charges are inside a box. Current density is the rate of charge moving through a volume: How many charges pass through a box in a given amount of time. Instead of using a box, people will also just talk about a boundary area and ask how many charges cross a boundary in a particular amount of time.

As you can see, these two ideas are intimately related to each other. Now, as to how these relate to nerves and electric impulse transmission, I am not an expert and do not know myself exactly.

Michael S. Pierce

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