Question

Why is the Local Standard Time fixed?

Answer 1

Local time of a place is fixed based on the movement of the Sun. Normally, it is established by the government of the concerned territory.

One of the most significant things about time zones is that the local time is persistent within the zone, while mean solar time fluctuates with longitude.  

Answer 2

Answer:

Generally, standard time agrees with the local mean time at some meridian that passes through the region, often near the center of the region. Historically, the concept was established during the 19th century to aid weather forecasting and train travel.

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