Find radiation resistance of a wire

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leonne
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Find radiation resistance of a wire...

Homework Statement


Find radiation resistance of a wire joining the two ends of a dipole.

Homework Equations



P=I2R


The Attempt at a Solution


Ok so to solve this problem I need to set the average power = to total power and solve for R
I thought P=I2R is the average power, but its not and not sure how to find it.
The solution first finds P=I2R =qo2w2sin2(wt) R than somehow from this they get (qo2w2R)/2
No idea how they got that, no other formula in the section seems to fit this.
 
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hi leonne! :smile:

(have an omega: ω :wink:)
leonne said:
The solution first finds P=I2R =qo2w2sin2(wt) R than somehow from this they get (qo2w2R)/2

the average value of sin2ωt is 1/2 :wink:

(because sin2ωt = (1 + cos2ωt)/2)

the usual formula is Paverage = Irms2R = Imax2R/2