Final answer:
Telephone signals travel through optical fibers in straight lines as laser-generated light, taking advantage of the low loss, high bandwidth, and reduced crosstalk properties of the fibers.
Step-by-step explanation:
Telephone signals travel as electromagnetic waves, which include a range of frequencies that can be used for communication. With the advent of modern technology, optical fibers have become the main medium for conveying telephone conversations and Internet communications. Lasers emit light through these fibers, where signal integrity is maintained due to the fibers' low loss, high bandwidth, and reduced crosstalk characteristics. These optical fibers can carry signals across long distances, both under the sea and underground, requiring less amplification and enabling multiple conversations through a single fiber.
Electromagnetic waves emitted by sources like antennas propagate in all directions, forming a complex radiation pattern. However, in the context of optical fibers, the signals follow a straight line through the fiber with very little loss, utilizing properties such as internal reflection to maintain the path of the signal.