Defining the electric current.

AI Thread Summary
The discussion revolves around clarifying the definition of electric current, particularly in relation to the dimensions of variables like area (A) and length (ΔL). Participants emphasize that A cannot be expressed as 1 divided by a length, highlighting the importance of dimensional analysis in understanding electric current. The original poster seeks to reconcile their lecture notes on Hertzian dipole antennas with the correct definitions and dimensions of variables. They are specifically trying to determine alternative meanings for ΔL if it cannot represent a length element. The conversation underscores the significance of accurate dimensional representation in physics.
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Hello.
I have attached a file containing a detailed question regarding the definition of the electric current. I'll be glad if someone can help me clarify this issue.
Thanks :redface:
 

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A is an area, so it can't be 1 divided by a length. You seem to be forgetting n and the fact that it isn't dimensionless.
 
willem2 said:
A is an area, so it can't be 1 divided by a length. You seem to be forgetting n and the fact that it isn't dimensionless.

Well, the problem is that I have read the summary I made for one of the lectures discussing the Hertzian dipole antenna, and \Delta L just appeared the way I wrote it in the attached file. In fact, I clearly noticed what you had written before posting this message/thread, but I still try to figure out if I can define n or \Delta L in different dimensions to get a correct expression for the electric current (I simply forgot to write some details down during the lecture and therefore now I try to understand what the lecturer meant..).
So what else could \Delta L represent if I rule out the possibility of a length element?
thanks :confused:
 

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