From west to east the six standard time zones in Europe are: (UTC/GMT -1) Azores Time Zone. (UTC/GMT +0) Greenwich Mean Time Zone, Western European Time Zone and Irish Time Zone. (UTC/GMT +1) Central European Time Zone.
Mechanical waves transport energy. This energy propagates in the same direction as the wave. Any kind of wave (mechanical or electromagnetic) has a certain energy. Mechanical waves can be produced only in media which possess elasticity and inertia. A mechanical wave requires an initial energy input. Once this initial energy is added, the wave travels through the medium until all its energy is transferred. In contrast, electromagnetic waves require no medium, but can still travel through one.
The simplest transmission media is a two-wire transmission line. There are two wires insulated from each other, open to free space. This type of media is suitable for connecting equipments that are separated less than 50 meters. This media can support data rate up to a theoretical maximum of 19 Kbps. A two-wire transmission media can directly connect two computers.