India

Written and reviewed by Subhra Gupta, Humanities faculty at UniDrill (M.A. Sociology, University of Delhi · 7 years teaching Humanities). Based on NCERT Geography Class XI (India: Physical Environment), Chapter 1.

Why does a clock in Kohima agree with one in Jaisalmer?

The sun rises in Arunachal Pradesh almost two hours before it rises in Gujarat. Yet the watches in Dibrugarh, Imphal, Bhopal and Chennai all show the same time. That is not a mistake. It is a decision made possible by the way India sits on the globe, and this short chapter is where CUET collects some of its most dependable, number-based questions: coordinates, distances, area, coastline and time.

India on the globe: the numbers to own

India's mainland runs from Kashmir in the north to Kanniyakumari in the south, and from Arunachal Pradesh in the east to Gujarat in the west. Learn the extent as one table, because most questions are simply a swapped number.

Why 30 degrees north to south is longer than 30 degrees east to west. Lines of latitude (parallels) are always the same distance apart, about 111 km per degree. Lines of longitude (meridians) are widest apart at the equator and meet at the poles, so a degree of longitude gets shorter as you move away from the equator. Across India a degree of longitude is only about 90 to 110 km. Thirty degrees of latitude therefore cover more ground than thirty degrees of longitude. This single idea answers a question that appears in almost every paper.

Pause and predict: at Kanniyakumari (about 8°N), which is longer: one degree of latitude or one degree of longitude?

Check your answer: one degree of latitude is still about 111 km. A degree of longitude at 8°N is only slightly shorter than at the equator, because the meridians have barely begun to converge. The gap grows steadily as you go north, which is why the difference is larger in Kashmir than in Kerala.

Nautical mile versus statute mile. The territorial limit uses the nautical mile, which is the longer unit.

Twelve nautical miles is therefore about 21.9 km, not 19 km. A question that swaps the two units is a trap, not a trick.

Latitude decides the climate zones

The Tropic of Cancer (23°30'N) cuts across the middle of the country. It passes through eight states: Gujarat, Rajasthan, Madhya Pradesh, Chhattisgarh, Jharkhand, West Bengal, Tripura and Mizoram. The southern part of India lies in the tropics, and the northern part lies in the sub-tropical (warm temperate) zone.

This one fact explains why India has such variety in landforms, climate, soil types and natural vegetation. Later chapters (climate, vegetation) keep returning to it.

Longitude and time: the standard meridian

Local solar time changes by 4 minutes for every degree of longitude, so the nearly 30 degrees of India's spread produce a gap of nearly two hours between the easternmost and westernmost points. If every town used its own sun time, railway timetables and offices would be chaos. So India picks one standard meridian, 82°30'E, and the whole country follows Indian Standard Time (IST), which is 5 hours 30 minutes ahead of Greenwich Mean Time.

Why 82°30'E and not 80°E or 85°E? Countries generally choose standard meridians in multiples of 7°30', because 7°30' equals exactly 30 minutes of time. Since 82°30' is eleven times 7°30', it works. The textbook asks you to name places on it, and Mirzapur in Uttar Pradesh is the usual answer.

Pause and predict: what would IST be relative to GMT if India had chosen 90°E?

Check your answer: 90°E is also a multiple of 7°30' (twelve times). Ninety degrees at 4 minutes per degree is 360 minutes, so the offset would be 6 hours ahead of GMT. Using the same working, 82°30' gives 330 minutes, which is 5 hours 30 minutes.

Two views. For the exam: India has a single standard meridian, 82°30'E, and one national time. Another reading: because the sun rises much earlier in the northeast, some people have argued for a second time zone for that region, while supporters of a single time stress administrative simplicity for railways, broadcasting and offices. Both arguments are part of the textbook's own question on whether India needs more than one standard time.

Beyond the textbook. For the exam: 82°30'E was chosen because standard meridians are multiples of 7°30'. In reality: it also sits close to the middle of India's longitudes. The midpoint of 68°7'E and 97°25'E is about 82°46'E, so the chosen meridian is a fair compromise for the whole country. Why it matters: a student who thinks the meridian was picked only because it is central will miss the 7°30' rule that questions test.

Size and its consequence: a country of contrasts

India's 3.28 million sq. km is 2.4 per cent of the world's land area, which makes it the seventh largest country. Six countries are larger: Russia, Canada, China, the USA, Brazil and Australia.

Size gives India physical diversity. You get lofty mountains in the north, large rivers such as the Ganga, Brahmaputra, Mahanadi, Krishna, Godavari and Kaveri, green forested hills in the northeast and the south, and the vast sandy expanse of Marusthali (the Thar). A traveller from Kashmir to Kanniyakumari, or from Jaisalmer to Imphal, crosses almost every type of landscape.

The Indian subcontinent and its passes

Bounded by the Himalayas in the north, the Hindukush and Sulaiman ranges in the north-west, the Purvachal hills in the north-east and the Indian Ocean in the south, the region forms a great geographic entity called the Indian subcontinent. It includes Pakistan, Nepal, Bhutan, Bangladesh and India. Sri Lanka and Myanmar are neighbours, but they are not counted in this five-country set.

The mountain wall made travel difficult and helped shape a distinct regional identity. Only a few passes allowed crossing.

Khyber and Bolan are in present-day Pakistan, which is why they are sometimes wrongly marked as Indian passes.

Coast and neighbours

The peninsula juts into the Indian Ocean, which divides into two arms: the Arabian Sea in the west and the Bay of Bengal in the east. India sits in the south-central part of Asia, so this maritime location links it to Africa, Europe, West Asia and East Asia by sea and air routes.

Two island countries in the Indian Ocean are India's neighbours: Sri Lanka and Maldives. Sri Lanka is separated from India by the Gulf of Mannar and the Palk Strait. A gulf is a large inlet of the sea into the land. A strait is a narrow stretch of water joining two larger water bodies. On land, the longest frontier India shares is with Bangladesh (over 4,000 km); the other land neighbours include Pakistan, China, Nepal, Bhutan and Myanmar.

Beyond the textbook. For the exam: the Indian subcontinent means India, Pakistan, Nepal, Bhutan and Bangladesh. In reality: the word is also used loosely in everyday and academic writing for the wider region, and some writers add Sri Lanka and the Maldives. The geographic definition above is what the exam uses. Why it matters: if an option reads "Myanmar" or "Sri Lanka" in a question on the subcontinent as defined here, it is the odd one out.

Key terms and people

Exam traps

60-second revision

Where this chapter connects

• Within this book: Structure and Physiography takes the physical diversity mentioned here and explains how it was built.
• Climate link: Climate uses the latitude, the Himalayan wall and the coastline from this chapter as its first causes of India's climate.
• Earth basics: Geography as a Discipline and Solar Radiation, Heat Balance and Temperature supply the latitude and longitude ideas used here.