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Among these frequency ranges, which one would contain VHF waves only?
  • A
    29 MHz to 132 MHz
  • B
    29 GHz to 132 GHz
  • C
    90 kHz to 295 kHz
  • D
    90 MHz to 295 MHz

Refer to figure.
Learning Objective List the bands of the frequency spectrum for electromagnetic waves: very low frequency (VLF): 3-30 kHz; low frequency (LF): 30-300 kHz; medium frequency (MF): 300-3 000 kHz; high frequency (HF): 3-30 MHz; very high frequency (VHF): 30-300 MHz; ultra-high frequency (UHF): 300-3 000 MHz; super high frequency (SHF): 3-30 GHz; extremely high frequency (EHF): 30-300 GHz.

Each frequency band is effectively a logarithmic band which begins at one frequency value, and ends at the frequency value 10x higher. They all begin with the number 3, and are of different orders of magnitude.

VHF is the best known frequency band by pilots, as that is the frequency our radios use for transmissions to ATC. VHF waves exist between frequencies of 30 MHz and 300 MHz. A good way of remembering all the frequency bands is having VHF as a "starter band", and we can say that a well known VHF frequency of 121.5 MHz is between 30 and 300 MHz, so therefore we can create the bands with frequencies above (UHF, SHF and EHF) and below that (HF, MF, LF and VLF), using multiples of 10.

There is a saying to remember the order, using the first letters, "Very Lovely Maidens Have Very Useful Sewing Equipment".

The only answer that exists completely between 30 and 300 MHz is "90 MHz to 295 MHz".

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