Geography Mixed Quiz: Set 10

The correct answer is A, the equator. A great circle is one whose plane passes through the centre of the sphere and which therefore divides it into two equal halves. Among the parallels only the equator satisfies this, which is why it separates the northern and southern hemispheres and is the longest parallel of all.

Option B, the Tropic of Cancer, and option D, the Tropic of Capricorn, lie 23.5 degrees away from the equator, so their planes are offset from the centre and the circles they form are smaller. Option C, the Arctic Circle, at 66.5 degrees north, is smaller still, because parallels shrink steadily towards the poles. Meridians behave differently: every meridian and its opposite meridian together make a full great circle, which is why the shortest air route between two distant cities follows a great circle and often looks curved on a flat map.

The correct answer is A, Two. Because of the gravitational pull of the moon and the sun, together with the centrifugal effect of the earth's rotation, most coasts see the sea rise and fall twice in a day. The moon's pull raises a bulge of water on the side of the earth facing it and another on the opposite side, and as the earth turns a place passes through both bulges in about twenty-four hours. These are called semi-diurnal tides, and successive high tides come about twelve hours and twenty-five minutes apart. Option B is wrong because no shore gets three tidal cycles in a day. Option C is wrong because four counts the individual tides — two high and two low — while the rise-and-fall cycle itself happens twice. Option D is wrong because a single daily high and low, called a diurnal tide, occurs only on a few coasts such as parts of the Gulf of Mexico. Exam tip: spring tides come at full moon and new moon when sun and moon pull in line, and neap tides at the quarters.

The correct answer is C, limestone. Limestone is a sedimentary rock made largely of calcium carbonate, and when heat and pressure recrystallise it without melting it, the result is marble, the stone used in the Taj Mahal and in the Dilwara temples.

Option A, sandstone, turns into quartzite under metamorphism, a rock so hard that it resists weathering and forms ridges. Option B, shale or clay, turns into slate, which splits into thin sheets and was long used for roofing and writing boards. Option D, granite, an intrusive igneous rock, turns into gneiss, recognised by its banded appearance. Since one or another of these pairs appears in nearly every paper, revise them as a single list: limestone to marble, sandstone to quartzite, shale to slate, granite to gneiss and coal to graphite.

The correct answer is A, Himadri Range. The Himadri, or Greater Himalaya, is part of the Himalayan system, the youngest fold mountains in India, formed as the Indian plate pushed into the Eurasian plate and folded up the sediments of the old Tethys Sea. The uplift began only about 50 million years ago and is still going on, which is why the region has frequent earthquakes. The Himadri is the highest and most continuous range, with an average height of about 6,000 metres and peaks such as Kanchenjunga and Nanda Devi. Within the Himalaya itself, the outer Shiwalik range is the youngest, but it is not among the options. Option B is wrong because the Aravalli is the oldest fold mountain range of India, worn down over hundreds of millions of years. Option C is wrong because the Western Ghats are the raised western edge of the ancient Deccan plateau. Option D is wrong because the Vindhyas are an old range of Peninsular India made of ancient sedimentary rocks. Exam tip: oldest range, Aravalli; youngest, the Himalaya, and within it the Shiwaliks.

The correct answer is B, Godavari, Krishna, Mahanadi, Tapi. The Godavari, about 1,465 km long, is the longest river of peninsular India and is called the Dakshin Ganga; it rises at Trimbakeshwar near Nashik in Maharashtra. The Krishna, about 1,400 km long, rises near Mahabaleshwar. The Mahanadi flows about 851 km from Chhattisgarh through Odisha to the Bay of Bengal, and the Tapi, about 724 km long, rises in Betul district of Madhya Pradesh and flows west into the Arabian Sea. Option A is wrong because it puts the Mahanadi first, though it is shorter than the Godavari, the Krishna and the Narmada. Option C is wrong because the Narmada, about 1,312 km long, is shorter than the Godavari, and the Mahanadi cannot come before the Godavari either. Option D is wrong because the Krishna is longer than the Narmada, so the Narmada cannot come second. Exam tip: peninsular rivers by length are Godavari 1,465, Krishna 1,400, Narmada 1,312, Mahanadi 851 and Tapi 724 km.

The correct answer is D, Tamil Nadu. The Shevaroy Hills, also spelt Servarayan, rise near Salem in Tamil Nadu and are part of the Eastern Ghats. Their best-known spot is the hill station of Yercaud, about 1,500 metres high, famous for coffee plantations, oranges and the Yercaud lake, which is why the range is sometimes called the "poor man's Ooty". The Shevaroys form a set with the other Eastern Ghats hills of Tamil Nadu, the Javadi, Kalrayan and Pachaimalai hills, and all four sit between the Palar and Kaveri river basins. A, Chhattisgarh, has the Maikal range and the Bastar plateau. B, Odisha, has the Garhjat hills and Mahendragiri in its stretch of the Eastern Ghats. C, Rajasthan, has the Aravalli range with Guru Shikhar as its highest point. Exam tip: Shevaroy, Javadi, Kalrayan and Pachaimalai are Tamil Nadu's Eastern Ghats hills; Yercaud sits on the Shevaroys.

The correct answer is B, Greenwich, the site of the old Royal Observatory near London. The meridian running through it was accepted as the zero meridian, from which all longitudes are counted east and west, and its local time is Greenwich Mean Time, the reference for the world's standard times.

Option A, Paris, is a strong distractor because France long used its own prime meridian through the Paris Observatory before the international agreement. Option C, Rome, and option D, Washington, were never adopted as the zero meridian, although several countries did use national meridians of their own in the nineteenth century. Remember the pair of extremes for this chapter: the equator is the reference for latitude and the Greenwich meridian is the reference for longitude, and the meridian directly opposite Greenwich, at 180 degrees, is the one the International Date Line broadly follows.

The correct answer is D, Vembanad Lake. Vembanad in Kerala is the longest lake in India, stretching about 96 km from Alappuzha to Kochi, and it is also the largest lake of Kerala. It is a brackish backwater lagoon separated from the Arabian Sea by a narrow barrier, it is a Ramsar wetland since 2002, and the famous Nehru Trophy snake-boat race is held on it at Punnamada every August. Willingdon Island, on which Kochi port stands, was raised inside this lake. A, Shivaji Sagar Lake, is the reservoir of the Koyna dam in Maharashtra, a man-made lake. B, Indira Sagar, is the reservoir of the Indira Sagar dam on the Narmada in Madhya Pradesh, the largest reservoir in India by water volume but not the longest lake. C, Chilika Lake in Odisha is the largest brackish-water lagoon in India and Asia by area, but it is shorter than Vembanad. Exam tip: longest lake Vembanad, largest brackish lagoon Chilika, largest freshwater lake Wular.

The correct answer is B, basalt. The Deccan Trap was formed by vast fissure eruptions in which lava spread over the surface and cooled quickly, giving a fine-grained extrusive igneous rock, basalt. Its weathering produces the black regur or cotton soil of Maharashtra, Madhya Pradesh and Gujarat.

Option A, granite, is also igneous but intrusive: it cools slowly deep inside the crust and therefore has large visible crystals. Option C, limestone, is a sedimentary rock of marine origin used in cement manufacture, not a lava rock. Option D, gneiss, is a metamorphic rock of the old peninsular shield, banded in appearance and derived from granite. The examiner is testing two ideas at once here, that basalt is extrusive and that the Deccan lava flows are the parent of black soil.

The correct answer is D, Altitude and slope determine the rate of humus formation. Altitude and slope, which together make up relief, decide how much soil collects at a place, not how fast humus forms. Humus is the dark organic matter made when dead leaves and animals rot, and its rate of formation depends on climate and on the living things in the soil: plants, animals and micro-organisms. NCERT lists five factors of soil formation. Parent rock gives the soil its colour, texture and minerals; climate, meaning temperature and rainfall, sets the rate of weathering and humus formation; relief, meaning altitude and slope, controls how much soil accumulates; time decides the thickness of the soil profile; and flora, fauna and microbes affect humus. A is wrong as a choice because temperature and rainfall really do control weathering. B is wrong because time does decide how thick the profile grows. C is wrong because parent rock does fix the colour of soil. Exam tip: relief = accumulation of soil; climate and organisms = humus; parent rock = colour and texture; time = thickness.

The correct answer is C, Mahi. The Mahi rises in the Vindhya hills in Dhar district of Madhya Pradesh, flows through the Banswara region of Rajasthan and then crosses Gujarat to fall into the Gulf of Khambhat, so it passes through three states. Like the Narmada, the Tapi and the Sabarmati, it is one of the few Indian rivers that flow west into the Arabian Sea. The Mahi is also known for crossing the Tropic of Cancer twice, a favourite fact of paper setters. Option A is wrong because the Ken flows only through Madhya Pradesh and Uttar Pradesh, where it joins the Yamuna. Option B is wrong because the Sonar stays within Madhya Pradesh and joins the Ken. Option D is wrong because the Betwa rises in Raisen district and joins the Yamuna in Uttar Pradesh, so it covers only two states. Exam tip: Mahi goes from Dhar through Rajasthan to Gujarat, three states, and crosses the Tropic of Cancer twice.

The correct answer is C, Neither I nor II. Both pairs are reversed: in Punjab rice is a commercial crop, while in Odisha it is a subsistence crop. The same crop can be commercial in one state and subsistence in another; it depends on why the farmer grows it. A subsistence crop feeds the farmer's own family, and a commercial crop is grown mainly for sale. Punjab and Haryana farmers do not eat much rice, yet they grow it on irrigated land with high-yielding seeds and sell almost all of it to the government at the minimum support price. In Odisha, West Bengal and Assam rice is the staple food, grown mostly on small rain-fed plots for the family's own kitchen. A is wrong because Punjab rice is sold, not eaten at home, so it is commercial. B is wrong because Odisha rice is largely eaten by the growers, so it is subsistence. D fails because neither pair is correct. Exam tip: NCERT line to remember, rice is commercial in Punjab and Haryana but subsistence in Odisha.

The correct answer is C, 66.5 degrees north. The Arctic Circle marks the latitude beyond which the sun stays above the horizon for the whole of at least one day in midsummer and below it for the whole of at least one day in midwinter, the phenomenon known as the midnight sun and the polar night.

Option A, 23.5 degrees north, is the Tropic of Cancer, the northern limit of the overhead sun. Option B, 45 degrees north, is merely the midpoint between the equator and the pole and has no special astronomical meaning. Option D, 90 degrees north, is the North Pole itself, the highest latitude that exists. The two numbers to fix are 23.5 and 66.5, and note that they add up to 90, since the tilt of the earth's axis of 23.5 degrees decides both of them.

The correct answer is C, a-iii, b-i, c-ii, d-iv. Gua and Noamundi, in West Singhbhum district of Jharkhand, are well-known iron ore mines of the Singhbhum–Keonjhar belt, which feeds steel plants such as the one at Jamshedpur. Balaghat district in Madhya Pradesh has the Malanjkhand copper mine, one of India's largest open-cast copper mines. The Amarkantak plateau, where the Narmada and the Son rise, has rich bauxite deposits, the ore of aluminium. Nellore district in Andhra Pradesh is a leading mica belt of India, along with Koderma in Jharkhand and Bhilwara in Rajasthan. Option A is wrong because it gives copper to Amarkantak and bauxite to Balaghat. Option B is wrong because it places iron ore at Amarkantak and bauxite at Gua and Noamundi. Option D is wrong because it puts iron ore at Balaghat, copper at Gua and Noamundi, and mica at Amarkantak. Exam tip: Gua–Noamundi iron ore, Malanjkhand (Balaghat) copper, Amarkantak bauxite, Nellore and Koderma mica.

The correct answer is B, sedimentary rocks. They are built up layer by layer as sediment settles over the remains of living things and hardens gently, so shells, bones and plant matter survive as fossils. The same layered basins hold coal and petroleum, which makes this family the most valuable one economically.

Option A, igneous rocks, form from molten magma or lava at temperatures that destroy every trace of organic material. Option C, metamorphic rocks, may begin as fossil-bearing sedimentary rock, but the heat and pressure of metamorphism deform and erase the fossils. Option D, plutonic rocks, is only another name for intrusive igneous rocks such as granite, so it fails for the same reason as option A. Remember that layering, or stratification, and fossils always point to the sedimentary family.

The correct answer is D, Brahmaputra river. National Waterway 2 is the Brahmaputra from Dhubri to Sadiya in Assam, a stretch of 891 km declared in 1988. It carries cargo and passengers through the Brahmaputra valley and connects with Bangladesh through the Indo-Bangladesh Protocol route. National Waterway 1, the Ganga–Bhagirathi–Hooghly system from Haldia to Prayagraj, is the longest at 1,620 km. The waterways are developed and run by the Inland Waterways Authority of India, headquartered at Noida. A is wrong because the West Coast Canal with the Champakara and Udyogmandal canals in Kerala is National Waterway 3. B is wrong because the East Coast Canal with the Matai river, in Odisha and West Bengal, is part of National Waterway 5. C is wrong because the Kakinada canal belongs to National Waterway 4, which links the Godavari and Krishna rivers with canals from Kakinada to Puducherry. Exam tip: NW-1 Ganga (Haldia–Prayagraj), NW-2 Brahmaputra (Dhubri–Sadiya), NW-3 West Coast Canal (Kerala).

The correct answer is C, (ii) (iii) (i) (iv). The Kaveri rises at Talakaveri in the Brahmagiri hills of Kodagu in Karnataka; the Sabarmati begins in the Aravalli hills of Mewar in Udaipur district of Rajasthan; the Tapti rises near Multai in Betul district, on the Satpura range of Madhya Pradesh; and the Damodar starts on the Chhotanagpur plateau of Jharkhand. An easy way to check: the Tapti and the Narmada are the two big west-flowing rift-valley rivers of central India, while the Damodar, once called the Sorrow of Bengal, is a river of the eastern coal belt. Option A is wrong because it sends the Kaveri to the Satpuras and the Tapti to the Mewar hills. Option B is wrong because it puts the Kaveri in the Mewar hills and the Sabarmati on the Chhotanagpur plateau. Option D is wrong because it links the Kaveri with Chhotanagpur and the Damodar with the Satpuras. Exam tip: Kaveri–Brahmagiri, Sabarmati–Mewar, Tapti–Multai on the Satpuras, Damodar–Chhotanagpur.

The correct answer is C, the 180 degree meridian, which lies in the Pacific Ocean opposite Greenwich. The line does not follow it exactly: it bends east and west to keep the eastern tip of Siberia, the Aleutian Islands and several Pacific island groups on one side, so that no country is left with two dates at the same moment.

Option A, the zero degree meridian, is the Prime Meridian at Greenwich, the starting line for longitude, not for dates. Option B, 90 degrees east, and option D, 90 degrees west, are ordinary meridians with no special role. The rule to remember for the crossing is that a traveller going from east to west across the line adds a day, while one going from west to east repeats the day just passed. This is why a voyage westward around the world appears to lose a calendar date unless the line is accounted for.

The correct answer is C, oxygen. Almost half the weight of the crust, about 46.6 per cent, is oxygen, because it is locked into the silicate minerals of which nearly all crustal rocks are made rather than existing as free gas.

Option A, silicon, comes second at about 27.7 per cent, and together with oxygen it forms the silica that gives the crust its character. Option B, aluminium, is third at about 8.1 per cent, and it is the most abundant metal in the crust, a fact often asked as a separate question. Option D, iron, follows at about 5 per cent in the crust, though it is the dominant element of the core, which is called Nife for nickel and iron. Keep two answers ready: oxygen for the most abundant element and aluminium for the most abundant metal.

The correct answer is D, A-iv, B-i, C-ii, D-iii. The Rapti rises in Nepal, flows past Gorakhpur in Uttar Pradesh and joins the Ghaghra, which then meets the Ganga. The Tista, or Teesta, rises from glaciers in Sikkim, cuts through the Darjeeling hills and joins the Brahmaputra, known there as the Jamuna, in Bangladesh. The Hiran is a small tributary of the Narmada that joins it from the north in Madhya Pradesh. The Purna rises in the Ajanta hills of Maharashtra and joins the Godavari; do not confuse it with another Purna that joins the Tapi. Option A is wrong because it sends the Tista to the Narmada and the Purna to the Brahmaputra. Option B is wrong because it links the Rapti with the Brahmaputra and the Hiran with the Godavari. Option C is wrong because it makes the Rapti a tributary of the Godavari. Exam tip: Rapti–Ghaghra, Tista–Brahmaputra, Hiran–Narmada, Purna–Godavari, and a second Purna joins the Tapi.