What is the length of each side of a resonant dipole to receive 12MHz?

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SUMMARY

The length of each side of a resonant dipole antenna designed to receive a frequency of 12MHz is 6.25 meters. This is derived from the formula λ = c/f, where λ equals the wavelength, c is the speed of light (3x10^8 m/s), and f is the frequency (12x10^6 Hz). The total dipole length is λ/2, resulting in 12.5 meters, which is then divided by two to obtain the length of each side as 6.25 meters. A resonant half-wave dipole consists of two quarter-wave elements, confirming the necessity of this division.

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amgc63
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I don’t understand why require to divide twice
Hi, a question:

Construct a resonant dipole to receive 12MHz.

Answer;

λ = c/f
= (3x10^8) / (12 x10^6)
= 25m
The dipole length λ/2 = 12.5m
The length of each side dipole is 12.5m/2 = 6.25m

Im confused, isn’t it the answer is 12.5m?
Why require to divide 12.5m/2 again to get the answer 6.25m?
Hope someone can explain.

Thanks in advance
 
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A half-wave dipole antenna is made up of two quarter-wave elements. A quarter-wave monopole antenna has one quarter-wave element over a ground plane...

1650297254798.png

https://www.antenna-theory.com/antennas/halfwave.php
 
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A resonant half-wave dipole has a length of λ/2 because the transit return time of the wave, there and back, must be equal to the period of the wave. Half of a resonant half-wave dipole will be λ/4.
 
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