Question

The value of longitude considered as the standard meridian of India is ……………………….
(A) ${82^ \circ }30'$ E
(B) ${68^ \circ }7'$ E
(C) ${97^ \circ }25'$ E
(D) ${82^ \circ }4'$ E

Answer 1

Hint: Longitude is the geographic coordinate and an imaginary line running through north south that indicates the east- west position of a point on the earth’s surface. Latitude is the geographic coordinate that defines the north- south position of a point on the earth’s surface and lines of constant latitude or parallel to the equator.

Complete step by step solution
A time zone is an area of the globe that notices a uniform standard time for lawful, commercial, and social purpose. Greenwich mean time is the mean solar time at the royal observatory in Greenwich, London. GMT was used as the international civil time standard, now replaced in that function by Coordinated Universal Time (UTC).
Indian Standard Time (IST) is the time observed in every part of India, with a time offset of UTC $ + 05:30$ . India does not notice daylight saving time (DSTu) or other seasonal adjustment. Indian Standard Time is computed based upon ${82^ \circ }30'$ E longitude, in Allahabad which is almost on the corresponding longitude reference line.
After independence of India, the Indian government made IST as the official time for the entire country, even though Kolkata and Mumbai reserved their own local time until $1948$ and $1955$ .

Thus the option (A) is correct

Note: The central observatory was shifted from Chennai to Shankargarh Fort in Allahabad district. So it would be close to UTC $ + 5:30$ as possible accepted by Himanshu Sharma. North east state people have a different “Tea Garden Time” to save daylight.