The area between 23.5° north of tropic of cancer and 23.5° South of tropic of Capricorn is called as tropical region here temperature is high around the year.
Why is the Indian Standard Time required from Gujarat to Arunachal Pradesh there is a time lag of 2 hours time along the standard Meridian of India (82°30'E) passing through Mirzapur (in Uttar Pradesh) is taken as the standard time for the whole country.