Final answer:
Cordless phones typically use 2.4 GHz and 5 GHz frequencies for communication, which are part of the radio-wave spectrum with reduced absorption by building materials. The 2.4 GHz band is utilized by Wi-Fi, Bluetooth, and microwaves, whereas the 5 GHz band provides faster Wi-Fi speeds with less interference.
Step-by-step explanation:
The two varieties that 2.4 GHz and 5 GHz cordless phones tend to come in are standard for wireless communications technologies. These frequencies are part of the radio-wave portion of the electromagnetic spectrum and are commonly used because they are less likely to be absorbed by building materials, which allows for clear communication through walls and other structures. The 2.4 GHz frequency is very popular and is used by a variety of devices including Wi-Fi networks, Bluetooth devices, and even microwave ovens, while the 5 GHz band is also used for Wi-Fi, offering typically faster speeds and less interference.
It is worth noting that these frequency bands are chosen to work around the absorption characteristics of common building materials and are used in everyday life for a variety of communications. For instance, 4G cellular signals operate at around 880 MHz, and GPS operates at 1.228 and 1.575 GHz, both being less likely to interfere with critical communications used in settings such as hospitals and airplanes.