Change set
Pick exam & year, then Go.
Question map
Indian Standard Time refers to local time of which one of the following places in India?
Explanation
Indian Standard Time (IST) is calculated based on the 82.5° E longitude, which serves as the Standard Meridian of India [3]. This meridian passes close to the east of Prayagraj, formerly known as Allahabad, in the state of Uttar Pradesh [1]. Specifically, the reference point is often identified as the clock tower in Mirzapur, which is located near Allahabad [t1][t4]. The selection of 82°30' E as the standard meridian ensures a uniform time across the country, balancing the nearly two-hour time lag between India's easternmost and westernmost points [c2][t2]. Consequently, IST is 5 hours and 30 minutes ahead of Greenwich Mean Time (GMT) [c1][c4]. While other cities like Bhopal, Delhi, and Lucknow have their own local solar times based on their specific longitudes, they all follow the official time derived from the Allahabad/Mirzapur reference meridian [c2][t8].
Sources
- [1] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 18: Latitudes and Longitudes > Indian Standard Time > p. 245
- [3] Physical Geography by PMF IAS, Manjunath Thamminidi, PMF IAS (1st ed.) > Chapter 18: Latitudes and Longitudes > Standard Time and Time Zones > p. 243