World Geography Questions and Answers

Answer: A

Where the zone of maximum stream velocity swings down towards the bed, the extra energy scours the channel and excavates a deep scoured pool.

Between the pools the velocity core lies higher in the flow, so material is deposited instead, building the shallow gravel bars called riffles. Pools and riffles therefore alternate along a channel.

Answer: C

Correct answer: Solar power

Solar power is renewable: the resource is replenished continuously on any human timescale, and using it does not diminish what is available tomorrow. Wind, hydro, tidal, geothermal and biomass belong to the same class. Coal and natural gas are fossil fuels, formed over hundreds of millions of years from buried organic matter, so the stock is fixed and burning it releases carbon dioxide that had been locked away. Uranium is the interesting case. Nuclear fission emits almost no carbon dioxide in operation, which makes it a low-carbon source, but the uranium ore itself is a finite mineral deposit, so it is not renewable. Low-carbon and renewable are two different tests, and nuclear passes one and fails the other. India’s renewable capacity has grown rapidly, with solar the fastest-expanding component, and a large share of it in Rajasthan, Gujarat and Karnataka.

Answer: D

All three statements are part of plate tectonic theory: new oceanic crust is created at mid-ocean ridges and the continents drift as the plates move; convection currents in the mantle drive that motion; and the oceanic crust is destroyed at subduction zones where one plate descends beneath another.

Creation, driving mechanism and destruction together make one coherent theory, so the combined choice is correct.

Answer: C

The Commonwealth of Independent States was founded on 8 December 1991 by Russia, Ukraine and Byelorussia (Belarus), whose leaders signed the Belovezha Accords declaring the USSR dissolved.

The other republics listed joined a fortnight later under the Alma-Ata Protocol, so they were members but not the original founders.

Answer: A

The Soviet Union comprised 15 union republics, all of which became independent states when it dissolved at the end of 1991.

Answer: A

The C horizon consists of weathered parent material not yet affected by translocation - broken-down rock that has not been reached by the leaching and accumulation which shape the A and B horizons above. Below it lies unweathered bedrock, the R horizon.

Answer: C

India's oldest oil refinery is at Digboi in Assam, commissioned in 1901 beside the oilfield discovered there in 1889.

It is one of the oldest working refineries anywhere in the world, though its capacity is small - about 0.65 million tonnes a year.

Answer: C

Correct answer: London

The Prime Meridian runs through Greenwich in southeast London, where the Royal Observatory stands, and it is the zero from which longitude is measured east and west. Unlike the equator, whose position is fixed by the Earth’s rotation, the choice of prime meridian is purely a convention. Several nations once used their own - Paris, Cadiz, Rio and others - and Greenwich was adopted internationally at the Washington conference of 1884, largely because most of the world’s shipping already used British charts. From it comes Greenwich Mean Time and, in modern practice, Coordinated Universal Time, against which every time zone is expressed as an offset. A small curiosity: modern satellite measurement places the true zero of longitude about 100 metres east of the brass line visitors stand on, because the reference frame now used differs slightly from the local vertical the Victorian astronomers worked with.

Answer: C

Correct answer: The continuous transformation of rock between igneous, sedimentary and metamorphic forms

The rock cycle is the set of processes by which rock is continually converted from one of the three classes into another, with no beginning or end. Magma cools to form igneous rock. Weathering and erosion break it into sediment, which is transported, deposited, compacted and cemented into sedimentary rock. Burial under heat and pressure converts that into metamorphic rock. Further heating melts it back to magma, and the cycle begins again. The important point is that the route is not fixed. Any rock type can become any other: metamorphic rock can be eroded into sediment without ever melting, sedimentary rock can be melted directly, igneous rock can be metamorphosed. The cycle is driven by two energy sources - the Earth’s internal heat, which powers plate tectonics, melting and metamorphism, and solar energy, which powers weathering, erosion and transport. One consequence is that the rock beneath our feet has been recycled many times, which is why almost no crust survives from the Earth’s first few hundred million years.

Answer: B

The Pacific is the largest ocean, covering about 165 million km² - about a third of the Earth's surface, and more than the Atlantic and Indian oceans together.

It also holds the deepest point on the planet, the Challenger Deep in the Mariana Trench.