India's longitudinal extent as observed is about 30O from west to east. This clearly indicates there would be around two hours time-lag from Gujarat to Arunachal Pradesh. To evade such discrepancies in geologic time, Indian standard time has been determined to supply the whole nation a regular time. The local time, 82O 30’E (the Standard Meridian) has been recognised as the Standard Time by the entire nation. Due to this, we observe the rise of the sun two hours earlier in Arunachal Pradesh and two hours later in Gujarat in the west but the clocks display the corresponding time.