Question

What is meant by Indian Standard Time? Why do we need a Standard Meridian for India?

Answer 1

Hint: The places that lie on different meridians possess different local times. It is, therefore, essential to accept the local time of a country’s central meridian as the standard time for the whole country to bring uniformity. In India, the local time at the Indian Standard Meridian is regarded as the standard time for the entire country.

Complete answer:
The uniform time calculated by the Standard Meridian of India is referred to as the Indian standard time (IST). In India, the longitude of 82°E (82° 30’ E) is considered as the standard meridian. The local time at this meridian is regarded as the standard time for the entire country.

Importance of Standard Meridian for India:
The places that lie on different meridians possess different local times, and due to this, there is a time lag of 2 hours from Gujarat to Andhra Pradesh. Therefore, time along India’s Standard Meridian (82°30’E) that passes via Mirzapur, Uttar Pradesh, is considered as the standard time for the entire country. Otherwise, different Indian regions would have different times that would create confusions, so one common standard time for the entire country was chosen to avoid problems.

Note: The Prime Meridian is the meridian of longitude that passes through the Greenwich observatory in London. It indicates the 0° longitude. More than one standard time has been adopted by some countries due to their great longitudinal extent. For example, Russia has as many as 11 standard times.