Calculating Electric Field for an FM Antenna in an EM Wave

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SUMMARY

The discussion focuses on calculating the electric field required to generate a voltage of 1.28 mV across a 1.10 m long FM antenna, which is aligned parallel to the electric field of an electromagnetic (EM) wave. The user initially calculated the energy density (u) as 1.45E-17 using the permittivity of free space (E0) and the root mean square electric field (Erms) of 0.00128V. They later recognized the simplicity of using the equation V = E * d to find the electric field, where V is voltage and d is the length of the antenna.

PREREQUISITES
  • Understanding of electromagnetic waves and their properties
  • Familiarity with the concepts of voltage, electric field, and antenna theory
  • Knowledge of the equation V = E * d for calculating electric fields
  • Basic grasp of energy density in electromagnetic fields
NEXT STEPS
  • Study the derivation and application of the equation V = E * d in electromagnetic contexts
  • Learn about the relationship between electric field intensity and power in antennas
  • Explore the concept of energy density (u) in electromagnetic waves
  • Investigate the role of antenna length and orientation in receiving EM waves
USEFUL FOR

Students in physics or electrical engineering, particularly those studying antenna design and electromagnetic theory, will benefit from this discussion.

skibum143
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Homework Statement


A 1.10m long FM antenna is oriented parallel to the electric field of an EM wave. How large must the electric field be to produce a 1.28 mV voltage between the ends of the antenna?


Homework Equations


u = EoErms^2
I = uc
Intensity = Power / area

The Attempt at a Solution


I found u to be 1.45E-17 using E0 and Erms of .00128V
Then I found I to be 4.35E-9
Then I found P to be 1.65E-8

I'm not sure I'm using the right equations to find the electric field, I don't really know what variable represents it?
 
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How about using the equation V=E*d?
 
yep, that's a lot easier. oops. thanks!
 

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