Geography Mixed Quiz: Set 15

The correct answer is C, Pacific Ocean. The circum-Pacific belt, popularly called the Ring of Fire, runs from the Andes of South America up through Mexico, the western coast of North America and the Aleutians, then down through Kamchatka, Japan, the Philippines and Indonesia to New Zealand. It follows the subduction zones where the Pacific plate is pushed beneath the surrounding plates, so it carries the greatest share of the world's active volcanoes and of its earthquakes.

Option A, the Atlantic Ocean, has the Mid-Atlantic ridge, where plates move apart and give quiet basaltic eruptions as in Iceland, but far fewer explosive volcanoes. Option B, the Indian Ocean, has volcanic activity along the Sunda arc and at islands such as Barren Island and Reunion, but no comparable ring. Option D, the Arctic Ocean, is the least active of the four. Link the Ring of Fire to subduction along the Pacific margin.

The correct answer is C, Mexico. Milpa is the name given to shifting cultivation in Mexico and in the neighbouring parts of Central America, where maize, beans and squash are grown together on a patch cleared from the forest. In shifting cultivation a plot is cleared by cutting and burning the trees, cropped for two or three years until the ash-fed soil loses its fertility, and then left fallow while the farmer moves to a fresh patch. Because the same practice grew up in forest belts across the world, it carries a different local name in each region. A is wrong because in India it is called jhum in the north-east, podu in Andhra Pradesh and bewar or dahiya in Madhya Pradesh. B is wrong because in Malaysia and Indonesia it is known as ladang. D is wrong because in Brazil it is called roca or coivara. Exam tip: milpa in Mexico, ladang in Malaysia, roca in Brazil, chena in Sri Lanka and jhum in north-east India.

The correct answer is B, the doldrums. Strong heating at the equator makes the air expand and rise, so surface pressure is low and horizontal winds are weak; sailing ships were often becalmed there. The rising air cools, condenses and gives the heavy convectional rainfall of the equatorial belt, and the zone where the trade winds of the two hemispheres meet here is the inter-tropical convergence zone.

Option A, the horse latitudes, is also a belt of calms but it lies near thirty degrees in the sub-tropical high pressure belt, where air sinks and the weather is dry. Option C, the roaring forties, names the strong westerlies of the southern ocean, the opposite of calm. Option D, the polar high, is the belt of cold heavy air over the poles from which the polar easterlies blow out.

The correct answer is C, Hiralal Chaudhuri. Hiralal Chaudhuri is called the father of the Blue Revolution, the sharp rise in India's fish production. Working as a fishery scientist, he achieved induced breeding of carp by hormone injection in 1957, a method that freed fish farmers from depending on wild seed collected from rivers and allowed hatcheries to supply fingerlings in large numbers. Aquaculture grew from there, and India is today among the largest fish producers in the world. Option A is wrong because Verghese Kurien led the White Revolution in milk, building the Amul model and Operation Flood. Option B is wrong because Sam Pitroda is linked with the telecom revolution and the spread of public call offices. Option D is wrong because M.S. Swaminathan is the father of the Green Revolution in wheat and rice. Exam tip: learn the colour revolutions together, Green for food grains, White for milk, Blue for fish, Yellow for oilseeds, Pink for prawns and Golden for horticulture.

The correct answer is D, Shield volcanoes. Basic lava is poor in silica, very hot and thin, so it travels a long way from the vent before it solidifies. Layer upon layer of such flows builds a wide dome with slopes of only a few degrees, shaped like a warrior's shield laid on the ground, of which Mauna Loa in Hawaii is the textbook example. Eruptions of this type are usually quiet rather than explosive.

Option A, composite or strato volcanoes such as Fujiyama and Vesuvius, are built of alternating layers of ash and viscous acidic lava and therefore rise as steep cones. Option B, cinder cones, are small steep hills built only of loose fragments thrown out around a vent. Option C, caldera volcanoes, are the most explosive kind, named after the wide hollow left when the summit collapses into an emptied magma chamber. The key idea to carry into the exam is that thin lava makes gentle slopes and thick lava makes steep ones.

The correct answer is A, Zanskar Range. Zoji La, or the Zojila pass, lies in the Zanskar range of the Himalayas at a height of about 3,528 metres. It is on the Srinagar to Leh highway between Sonamarg in the Kashmir valley and Drass in the Kargil district, and it is the gateway to Ladakh. Heavy snow closes it in winter, which is why the Zojila tunnel is being built to keep the route open through the year and give the armed forces year-round access to Ladakh. Option B is wrong because the Ladakh range holds the Khardung La and Chang La passes. Option C is wrong because the eastern Karakoram range holds the Karakoram pass and Saser La on the old trade route to Central Asia. Option D is wrong because the Dhauladhar range runs through Himachal Pradesh above Dharamshala and Kangra. Exam tip: Zoji La in the Zanskar range for Kashmir to Ladakh, Khardung La in the Ladakh range beyond Leh.

The correct answer is C, the tropical easterly jet. In summer, as the subtropical westerly jet withdraws to the north of the plateau of Tibet, an easterly jet stream forms in the upper air over peninsular India and blows from east to west. Its appearance goes with the burst of the south-west monsoon, and its strength is linked by meteorologists to the performance of the monsoon.

Option A, the polar front jet, blows in the upper air above the meeting of polar and tropical air in the middle latitudes and is not a feature of the Indian peninsula. Option B, the subtropical westerly jet, lies south of the Himalaya in winter and brings the western disturbances; it is present in the Indian region, but in the cold weather season, not in the monsoon. Option D, the polar night jet, forms in the winter stratosphere over the polar regions.

The correct answer is A, Dang. Dang is not a South Indian tribe. The name belongs to the Dangs district of southern Gujarat, whose tribal people are mainly Bhil, Warli and Konkana, all of western India. The other three are communities of the Nilgiri hills, where Tamil Nadu, Kerala and Karnataka meet. The Toda are pastoralists known for their barrel-shaped huts and their buffalo-centred rituals. The Badaga are farmers of the Nilgiri plateau who speak a tongue close to Kannada. The Irula, a Scheduled Tribe of Tamil Nadu, are known for snake catching and for collecting forest produce. Option B is wrong because the Toda are the best known tribe of the Nilgiris. Option C is wrong because the Badaga live on the same plateau, around Udhagamandalam. Option D is wrong because the Irula are spread across Tamil Nadu and Kerala. Exam tip: remember Toda, Kota, Kurumba, Badaga and Irula as the five main Nilgiri tribes, and place Bhil, Warli and the Dangs in Gujarat and Maharashtra.

The correct answer is D, Seismograph. A seismograph, also called a seismometer, senses the shaking of the ground and draws it as a wavy line called a seismogram. A heavy mass hangs so that it stays almost still while the frame moves with the earth, and the difference between the two is recorded. From the gap between the arrival of the faster P waves and the slower S waves at three or more stations, scientists work out the epicentre, and from the size of the waves they work out the magnitude. Option A is wrong because a speedometer shows the speed of a vehicle. Option B is wrong because an odometer measures the distance a vehicle has travelled. Option C is wrong because the Richter scale is a scale, not an instrument: it puts a number on the energy of a quake using the readings a seismograph has already made, and each whole step means about 32 times more energy. Exam tip: seismograph records, Richter scale measures magnitude, Mercalli scale measures the damage felt.

The correct answer is D, Sikkim. Sikkim does not touch Myanmar. Its neighbours across the border are Nepal to the west, China in the north and east, and Bhutan to the south-east. Only four Indian states share the border with Myanmar - Arunachal Pradesh, Nagaland, Manipur and Mizoram - and that border runs for about 1,643 km. Option A is wrong because Arunachal Pradesh meets Myanmar along its south-eastern edge. Option B is wrong because Mizoram has a long stretch of the Myanmar border besides its border with Bangladesh. Option C is wrong because Manipur meets Myanmar on the east, and Moreh in Manipur is the main trading town on that border. Sikkim is India's least populated state and shares borders with three countries, but Myanmar is not one of them. Exam tip: remember the Myanmar border states as A-N-M-M - Arunachal Pradesh, Nagaland, Manipur and Mizoram.

The correct answer is C, El Nino. El Nino is the warming of the surface water of the central and eastern Pacific, and it weakens the trade winds that normally blow from east to west across that ocean. In normal years those winds push warm water towards Australia and Indonesia, letting cold water rise along the coast of Peru. When the pressure pattern flips, the winds slacken or even reverse, warm water spreads east, and the upwelling off South America stops, which hurts the anchovy catch. El Nino usually means a weaker monsoon and drier conditions over India. Option A is wrong because the Coriolis force, caused by the earth's rotation, only deflects winds and does not weaken them. Option B is wrong because a Mango Shower is a local pre-monsoon rain of Kerala and Karnataka. Option D is wrong because La Nina is the opposite phase, with cooler Pacific water and stronger trade winds. Exam tip: El Nino means warm Pacific, weak trade winds and a weak Indian monsoon; La Nina is the reverse on all three.

The correct answer is D, Tide. A tide is the regular rise and fall of sea level caused by the gravitational pull of the Moon and, to a smaller extent, the Sun, together with the centrifugal force of the spinning earth. Most coasts get two high tides and two low tides in about 24 hours and 52 minutes. When the Sun, Moon and Earth line up at new moon and full moon, the pulls add up and give the high spring tides; when the Sun and Moon are at right angles in the first and third quarters, the pulls work against each other and give the low neap tides. Tides help ships enter ports and are used for tidal power. Option A is wrong because waves are made by wind blowing over the surface. Option B is wrong because a tsunami is a single train of huge waves set off by an undersea earthquake or landslide. Option C is wrong because currents are steady horizontal flows of water such as the Gulf Stream. Exam tip: spring tides at full and new moon, neap tides in the quarters.

The correct answer is B, P waves. P waves, or primary waves, are longitudinal: the particles of the medium move back and forth along the same direction in which the wave travels, squeezing and stretching the rock like a sound wave. They are the fastest seismic waves, so they reach a recording station first and give the quake its early warning. P waves pass through solids, liquids and gases alike, which is how scientists learned that the earth's outer core is liquid - S waves die out there and leave a shadow zone. Option A is wrong because L waves, the surface or long waves, arrive last, travel along the crust and cause the most destruction. Option C is wrong because there is no seismic wave called an N wave. Option D is wrong because S waves, or secondary waves, are transverse: particles move at right angles to the direction of travel, and they can pass only through solids. Exam tip: P longitudinal and fastest, S transverse and solids only, L surface and most damaging.

The correct answer is B, North Atlantic Ocean. The Sargasso Sea lies in the middle of the North Atlantic and is the only sea in the world with no coastline. Instead of land, it is bounded by four ocean currents that circle clockwise around it: the Gulf Stream on the west, the North Atlantic Current on the north, the Canary Current on the east and the North Atlantic Equatorial Current on the south. Because it sits in the calm centre of this gyre, its water is warm, clear and very salty. It is named after sargassum, a brown seaweed that floats on its surface in huge mats, and it is the breeding ground of the American and European eels. Option A is wrong because the Arctic Ocean lies around the North Pole, far from this sea. Option C is wrong because the Sargasso Sea is north of the equator, not in the South Atlantic. Option D is wrong because the Indian Ocean is on the other side of Africa. Exam tip: Sargasso Sea means North Atlantic, no coastline, walled by currents, named after floating seaweed.

The correct answer is D, Polar Easterlies. The polar easterlies blow out of the high pressure belts over the poles towards the sub-polar low pressure belts, so they carry extremely cold and dry air. Cold air holds very little moisture, which is why these winds bring almost no rain and the polar regions are counted among the driest places on earth. They are one of the three planetary wind systems, along with the trade winds and the westerlies, and where they meet the warmer westerlies near sixty degrees latitude they form the polar front, the birthplace of temperate cyclones. Option A is wrong because monsoon winds reverse with the season and the summer monsoon is warm and heavy with moisture. Option B is wrong because the westerlies, blowing from the sub-tropical highs towards the sub-polar lows, bring rain to the western margins of continents. Option C is wrong because the trade winds blow towards the equator and are warm and moist over the oceans. Exam tip: trades from the east near the equator, westerlies in the middle latitudes, easterlies again at the poles.

The correct answer is C, Palk Strait – Palk Bay – Gulf of Mannar. Moving south between Tamil Nadu and Sri Lanka, you pass the strait first, then the bay, then the gulf. The Palk Strait is the northern channel that links the Bay of Bengal with Palk Bay, between Point Calimere in Tamil Nadu and the Jaffna peninsula of Sri Lanka. Palk Bay is the shallow water body just south of it. It is closed on the south by the chain of Pamban (Rameswaram) Island, Adam's Bridge (Ram Setu) and Mannar Island, and beyond that chain lies the Gulf of Mannar, which opens into the Indian Ocean and is a marine biosphere reserve known for coral reefs and dugongs. Option A is wrong because it starts with the Gulf of Mannar, the southernmost of the three. Option B is wrong because it puts the Gulf of Mannar above Palk Bay. Option D is wrong because Palk Bay lies south of Palk Strait, not north of it. Exam tip: from north to south, strait, bay, Adam's Bridge, then the Gulf of Mannar.

The correct answer is B, Westerlies Winds. The westerlies blow from the subtropical high pressure belt towards the subpolar low, which makes them south-westerly in the northern hemisphere and north-westerly in the southern. Between 40 and 50 degrees south there is almost no land to slow them down, so over the Southern Ocean they blow strong and steady all year and sailors named them the Roaring Forties. Further south they are called the Furious Fifties and the Shrieking Sixties. Option A is wrong because the polar easterlies are cold, dry winds that move from the polar high towards the sixty degree latitudes. Option C is wrong because the trade winds blow from the subtropical highs towards the equator, north-easterly above the equator and south-easterly below it, and once carried sailing ships on their trade routes. Option D is wrong because the doldrums is not a wind at all but the belt of calm near the equator along the inter-tropical convergence zone. Exam tip: forties roar, fifties are furious, sixties shriek, and all three are westerlies.

The correct answer is C, Kali and Teesta. The Himalayas, about 2,400 km long, are divided from west to east into regions marked by river valleys, and the Nepal Himalayas lie between the Kali in the west and the Teesta in the east. This is the highest stretch of the whole range and holds Mount Everest as well as Kanchenjunga on the Nepal–Sikkim border. The Kali forms the border between Uttarakhand and Nepal, and the Teesta flows through Sikkim before entering West Bengal. Option A is wrong because the Sutlej and the Dihang together cover almost the whole range and do not mark any single section. Option B is wrong because the land between the Sutlej and the Kali is the Kumaon Himalayas. Option D is wrong because the land between the Teesta and the Dihang is the Assam Himalayas. West of the Sutlej, up to the Indus, lie the Punjab Himalayas, also called the Kashmir and Himachal Himalayas. Exam tip: Indus–Sutlej Punjab, Sutlej–Kali Kumaon, Kali–Teesta Nepal, Teesta–Dihang Assam.

The correct answer is C, The air always moves from high pressure areas to low pressure areas. Air flows from where pressure is high to where it is low, and that moving air is what we call wind; the greater the difference in pressure, the stronger the wind. The Coriolis force then bends this flow, to the right in the Northern Hemisphere and to the left in the Southern. Option A is wrong because high pressure means sinking air, which brings clear skies and dry weather. Option B is wrong because low pressure means rising air that cools and condenses, so it brings clouds and rain. Option D is wrong because air pressure is highest at sea level, about 1,013 millibars, and falls as one goes up and the air thins. Pressure is measured with a barometer and shown on weather maps by isobars, the lines joining places of equal pressure. Exam tip: high pressure means sinking air and clear weather; low pressure means rising air, clouds and rain.

The correct answer is C, Deccan Plateau. The Deccan plateau is the large triangular block of the Peninsular plateau south of the Narmada, bounded by the Satpura and Vindhya ranges in the north, the Western Ghats in the west and the Eastern Ghats in the east, with an average height of about 600 metres. It is higher in the west, up to 900 to 1,200 metres along the Western Ghats, and tilts east, so the Godavari, Krishna and Kaveri flow east into the Bay of Bengal. Its north-western part is the Deccan Trap of basalt lava, which weathers into black cotton soil. Option A is wrong because the Marwar plateau is a low upland of eastern Rajasthan, drained by the Banas. Option B is wrong because the Meghalaya plateau is a detached block in the north-east, made of the Garo, Khasi and Jaintia hills. Option D is wrong because the Chota Nagpur plateau lies in Jharkhand, drained by the Damodar and rich in coal and iron. Exam tip: Deccan = between Satpura, Western Ghats and Eastern Ghats, high in the west, sloping east.