The west to eats extent leads to difference in local time from meridian to meridian. The local time changes by four minutes for every one degree of longitude. The sun rises two hours earlier in the east, Le. Arunachal Pradesh than in the west, ie. (Gujarat). The local time of longitude of 82° 30′ E has been taken as the Indian Standard Time. This longitude is also known as the Standard Meridian of India. Its time is taken as the standard throughout the country.
