World Geography Questions and Answers

Answer: B

Correct answer: Earth

Earth is the largest and most massive of the four terrestrial planets, slightly ahead of Venus, with Mars about half its diameter and Mercury smaller still. The inner planets share a common structure - an iron core, a silicate mantle and a solid crust - and are dense and small compared with the gas giants beyond the asteroid belt. That division arose in the early solar system, when the heat of the young Sun drove volatile material outward, leaving only rock and metal to condense close in. Earth is distinguished among them by liquid water at the surface, plate tectonics, an oxygen-rich atmosphere and a strong magnetic field generated by its liquid outer core - which shields the atmosphere from being stripped by the solar wind, a protection Mars lost. It is also the densest planet in the solar system.

Answer: C

Starlight is dimmed and reddened by both the earth's atmosphere and interstellar dust. The atmosphere scatters and absorbs light on its way to the ground, and dust between the stars does the same over far greater distances - which is why telescopes are placed on mountains and in orbit.

Answer: C

The magnetosphere is most disturbed during the main phase of a magnetic storm, when the ring current intensifies and the horizontal field component drops sharply. The initial and recovery phases bracket it.

Answer: C

Asia accounts for about 30 per cent of the world's land area, roughly 44.6 million km² out of about 149 million - a larger share than any other continent.

It also holds about 60 per cent of the world's population.

Answer: A

Phosphates are the mineral group in which one or more metallic elements are combined with the phosphate radical, PO₄³⁻.

Apatite, Ca₅(PO₄)₃(F,Cl,OH), is the commonest member and the chief source of phosphate fertiliser. The other formulae listed are not the phosphate radical.

Answer: C

Aconcagua in Argentina, at 6,961 m, is the highest point in South America and the highest anywhere outside Asia.

McKinley is North America's highest, Elbrus Europe's, and Kosciuszko the highest on the Australian mainland.

Answer: B

Evaporation alone would not complete the cycle - the vapour must be carried from where it forms to where it falls. The movement of water vapour in the atmosphere is therefore the other essential process, since most rain falls far from the ocean surface it evaporated from.

Tides and currents move liquid water within the sea and add nothing to the exchange between ocean and land.

Answer: C

Mindanao is the southernmost large island of the Philippines and so lies in the Pacific Ocean, on the western side of that ocean.

Answer: C

The ionosphere is the electrically charged region of the upper atmosphere, encompassing the thermosphere and the exosphere. Solar radiation ionises the thin gas there, which is what makes long-distance radio reflection possible.

Answer: C

Regur is the local name for the black cotton soil of the Deccan, formed by the weathering of the Deccan lava. It is rich in clay, swells when wet and cracks deeply when dry, and holds moisture so well that it grows cotton without irrigation.

It covers much of Maharashtra, Madhya Pradesh and Gujarat.