Why do we have different time zones 🤔? Because we’ve different watches? No!!
Our earth rotates on its owns Axis. Due to this rotation, different parts of the earth receive different amounts of sunlight.
Thus causing morning, noon, evening and night. Now, if we had one time zone, then 12 pm would be noon in some places. But it would be night or evening at other places which would be inconvenient.
Hence, scientists made different timezones according to the earth’s rotation with respect to the sun. But how?
How time zones were decided?
The earth makes one full 360 degrees rotation in 24 hours.
This means in one hour, the earth moves by 15 degrees.
360 degrees / 24 hours = 15 degrees in 1 hour
Using this information, scientists divided the planet into 24 sections or time zones. Thus currently, we’ve 24 different timezones.
Each section or region was about 15 degrees wide and had a specific standard time.
Want to learn more about Facts, History and Researches? Checkout out blog page : Click Here
Time zone conversions:
Conversion between time zones obeys the relationship
“time in zone A” − “UTC offset for zone A” = “time in zone B” − “UTC offset for zone B”,
in which each side of the equation is equivalent to UTC. (The more familiar term “UTC offset” is used here rather than the term “zone designator” used by the standard.)
The conversion equation can be rearranged to
“time in zone B” = “time in zone A” − “UTC offset for zone A” + “UTC offset for zone B”.
For example, the New York Stock Exchange opens at 09:30 (EST, UTC offset=−05:00). In Los Angeles (PST, UTC offset= −08:00) and Delhi (IST, UTC offset= +05:30), the New York Stock Exchange opens at
time in Los Angeles = 09:30 − (−05:00) + (−08:00) = 06:30.
time in Delhi = 09:30 − (−05:00) + (+05:30) = 20:00.
These calculations become more complicated near a daylight saving boundary (because the UTC offset for zone X is a function of the UTC time).
The table “Time of day by zone” gives an overview on the time relations between different zones.
Source: Wikipedia
