World Geography - 1 (Gen. Studies)

Availability of various rock forming elements (in percent) in earth’s crust (in % mass) is
Oxygen – 46.6
Silicon – 27.7
Aluminium – 8.1
Iron – 5.0

Igneous rocks are divided into two main categories: plutonic rock and volcanic rock. Plutonic or intrusive rocks result when magma cools and crystallises slowly within the earth's crust. A common example of this type is granite. Volcanic or extrusive rocks result from magma reaching the surface either as lava or fragmental ejecta forming minerals such as pumice or basalt.

Time between two observe passages of a star over the same meridian of longitude is called Sidereal day.
Sidereal day = 23 hours 56 min. 4.09 sec.

Frost is the weather condition that occurs when the air temperature is at or below 0^o.

Canada, specifically Alberta, holds the world's largest known deposits of tar sands (oil sands). The Athabasca oil sands in Alberta are the most significant tar sand resource globally. While tar sands exist elsewhere, Canada's deposits are by far the largest and most economically significant.

Biosphere reserves face significant threats from various forms of pollution including air pollution, water contamination, and industrial waste. Pollution disrupts delicate ecological balances, harms wildlife, and degrades habitat quality. While rainfall and soil erosion are natural processes, and population rate affects many ecosystems, pollution represents the most direct and widespread anthropogenic threat to protected areas.

Ecosystem means interdependence of living beings for survival.

The Earth Summit (UNCED - United Nations Conference on Environment and Development) was held in Rio de Janeiro, Brazil in June 1992. This landmark global conference addressed environmental issues and produced key agreements including the Convention on Biological Diversity and the Framework Convention on Climate Change.

Isohyets is the correct answer because they are lines on a map connecting points with equal rainfall. Isolines is the general term for any line connecting equal values, Isodrums is not a standard term, and Isotherms connect points of equal temperature - only Isohyets specifically refers to rainfall.

The Bushmen (also known as San people) are indigenous to Southern Africa and traditionally inhabit the Kalahari Desert region spanning Botswana, Namibia, and South Africa. The Thar Desert is in India/Pakistan, Atacama is in South America, and Great Victoria is in Australia - none of these are Bushmen territories.

Brazil is the world's largest bauxite producer, South Africa dominates gold production, USA is a major copper producer, and Malaysia historically led in tin mining. The matching in Option A correctly pairs each mineral with its principal producer. This tests knowledge of global mineral distribution patterns.

Birth-rate is conventionally expressed as births per 1000 people per year. This standardized measurement allows for easy comparison between different populations and is the universally accepted demographic indicator.

The Canadian Pacific Railway is a transcontinental railway connecting Montreal (in Quebec) on the east coast to Vancouver (in British Columbia) on the west coast. It was completed in 1885 and was crucial to Canada's development, linking the country from Atlantic to Pacific.

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Bass Strait separates Tasmania (the island state) from mainland Australia. Named after explorer George Bass, it connects the Indian Ocean to the Tasman Sea. The other straits are in different regions: Sunda (Indonesia), Kanmon (Japan), and Tiran (Red Sea near Egypt).

Correct Answer: Asia

The Mariana Trench in the western Pacific Ocean is the deepest oceanic trench, reaching approximately 11,034 meters (36,201 feet) at its deepest point (Challenger Deep). The Tonga Trench, Japan Trench, and Kermadec Trench are all deep but none exceed the Mariana Trench.

Peat, bituminous, and lignite are all types of coal - sedimentary rocks formed from compressed plant matter. Graphite, however, is a mineral (a form of carbon) formed through metamorphic processes, not from the coal formation pathway. It has a completely different origin and crystal structure.

Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate (CaCO₃).

This desert is sterile because it is blocked from moisture on both sides by the Andes Mountains and by the Chilean Range.

The Kalahari is not a true desert but a semi-arid region. Its aridity is primarily due to its location on the western coast within the tropical high-pressure belt (around 30°S), where descending air masses create dry conditions. While cold currents can influence coastal deserts, the Kalahari's position is more significant. The primitive nature of local populations has no effect on climate.

Nile is the longest river (length = 6653 km).

The Mid-Atlantic Ridge is a classic example of a diverent plate boundary where tectonic plates are moving apart. As the plates separate, magma rises to create new oceanic crust, causing seafloor spreading. Convergent boundaries involve plates coming together, transform boundaries involve plates sliding past each other, and 'spreading boundary' is not a standard geological term.

The India-Australia-New Zealand Plate (also called the Indo-Australian Plate) is one of the major tectonic plates covering approximately 0.2% of Earth's surface. The Philippine Plate, Arabian Plate, and Cocos Plate are smaller, minor plates. Major plates include: Pacific, North American, South American, Eurasian, African, Indo-Australian, and Antarctic plates.

Earth's shape is an oblate spheroid - slightly flattened at the poles and bulging at the equator. This is caused by Earth's rotation. The centrifugal force from rotation is strongest at the equator, causing material to bulge outward there. The equatorial diameter is about 43 km greater than the polar diameter. Revolution (orbit around the Sun) and atmospheric pressure do not affect shape.

S waves (shear waves) can only propagate through solids because they require the medium to resist shear stress. Liquids cannot support shear stress, so S waves cannot travel through them. This is why S waves cannot pass through Earth's liquid outer core. The statement 'S waves propagate through liquids' is incorrect, which is exactly what the question asks for (which statement is NOT correct).

Natural hazards are hazards which are caused because of natural phenomena (hazards with meteorological, geological or even biological origin). Examples of natural hazards are cyclones, tsunamis, earthquake and volcanic eruption which are exclusively of natural origin. Landslides, floods, drought, fires are socio-natural hazards since their causes are both natural and man made. For example flooding may be caused because of heavy rains, landslide or blocking of drains with human waste.

This is a tricky question. Most of the students may wrongly mark option 3 as their answer, but it should be noted that convectional currents occur in the mantle, and not in the crust.

The planet Earth is made up of three main shells: very thin and brittle crust, mantle and core. Mantle and core are each divided into two parts. Although core and mantle are equal in thickness, core actually forms only 15 percent of the earth's volume, whereas mantle occupies 84 percent. The crust makes up the remaining 1 percent.