Ron wrote:
On Sun, 09 May 2004 17:26:05 GMT, Dave Shrader
wrote:
SNIP
So you can use the formula I^2*R (which is for finding P) without
knowing the variable "I" to find the resistance (Ra)?
I don't think so. Unless you have a magic wand, Harry Potter :-)
Ron
You certainly can!!
Total power to the antenna SYSTEM = I^2*(Rr + Ra + Rg).
Total power radiated = I^2*(Rr).
When you divide the two terms to get efficiency the I^2 term cancels.
This leaves Rr/(Rr + Ra + Rg). The current terms drops right out!!
DD
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