Final answer:
Frequencies for TV-reception antennas are calculated using the relationship between wave speed, wavelength, and frequency. The ideal length of the antenna is half of the wavelength of the channel signal, and the polarization and orientation of the antenna affect reception. Additionally, observed frequencies are influenced by the relative motion between the source and the observer due to the Doppler effect.
Step-by-step explanation:
The questions posed relate to the frequencies of electromagnetic waves and their applications in technologies like VOR airway navigation, radio communication, and antenna design. For example, the ideal length of TV-reception antennas for Very High Frequency (VHF) is half the wavelength of the signal to be received. Given the lengths of 1.94 m and 0.753 m for particular channels, the frequencies can be found by using the relationship between the speed of light, wavelength, and frequency (c = λf). Using this equation, the frequencies for the respective channels can be calculated as follows:
• For 1.94 m long wires: f = c/λ = (3 × 10^8 m/s) / (2 × 1.94 m) ≈ 77.32 MHz
• For 0.753 m long wires: f = c/λ = (3 × 10^8 m/s) / (2 × 0.753 m) ≈ 199.47 MHz
These frequencies correspond to VHF television channels. Additionally, the received signal is related to the orientation of the receiving antenna with respect to the transmitting antenna's polarization. Lastly, frequencies observed by stationary people and moving engineers relate to the Doppler effect, where the observed frequency shifts depending on the relative motion between the source and the observer.