Where in the world does time begin and end?

Answer 1

Time constantly travels around the world, from east to west, at the rate of 1 hour per 15 degrees of longitude. The continental U.S., for example, covers roughly 60 degrees of longitude and thus 4 time zones. By convention and to simplify our life, clock times within the whole of a zone are considered to be the same (with some exceptions). So when, for example, the time in New York City, in the eastermost time zone of the U.S., is 10 a.m., the clock time in L.A., 3 zones to the west, is only 7 a.m. As the 10 a.m. time moves westward from New York, 10 a.m. moves from the Eastern to Central to Mountain and then Pacific time zones, one hour at a time.