World Geography Questions and Answers

Answer: C

The Sun's diameter is about 1,392,000 km, that is roughly 14 lakh kilometres - some 109 times the Earth's diameter of 12,756 km.

Put another way, about 1.3 million Earths would fit inside it, and it holds 99.8 per cent of all the mass in the solar system.

Answer: A

Outward from the Sun the order is Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune.

The four inner planets are small and rocky; beyond the asteroid belt come the four giants. Uranus comes before Neptune, and Earth before Mars, which is where the other options go wrong.

Answer: D

The Moon's diameter is about 3,475 km - a little over a quarter of the Earth's 12,756 km.

That ratio is unusually large for a moon, which is why the Earth–Moon pair is sometimes described as a double planet.

Answer: D

Nitrogen is the most abundant gas in the atmosphere, making up about 78 per cent of dry air by volume.

Oxygen accounts for about 21 per cent, argon for 0.93 per cent and carbon dioxide for only about 0.04 per cent - so nitrogen alone outweighs everything else combined.

Answer: B

Pluto was reclassified as a dwarf planet by the International Astronomical Union in 2006. It meets two of the three tests for a planet - it orbits the Sun and is round under its own gravity - but it has not cleared its orbital neighbourhood, sharing the Kuiper Belt with many similar bodies.

Mercury, Mars and Uranus remain full planets.

Answer: A

The mantle is about 2,900 km thick, reaching from the base of the crust down to the core boundary.

It makes up roughly 84 per cent of the Earth's volume and about two-thirds of its mass, and it is the convection within it that drives the movement of the plates above.

Answer: A

Saptarishi - 'seven sages' - is the Indian name for the seven bright stars of Ursa Major, the group known in English as the Plough or the Big Dipper.

Two of them, the Pointers, line up on Polaris, which is why the group has served as a night-time compass in every tradition that named it.

Answer: C

The deepest point of the Mariana Trench, Challenger Deep, lies about 10,994 m below sea level - the deepest place in any ocean.

Mount Everest, at 8,849 m, would be submerged in it with more than two kilometres of water to spare.

Answer: C

The atmosphere has five distinct layers, distinguished by whether temperature rises or falls with height: the troposphere, stratosphere, mesosphere, thermosphere and exosphere.

Each is separated from the next by a boundary named for it - the tropopause, stratopause and mesopause - at which the temperature trend reverses.

Answer: B

The autumnal equinox falls on about 23 September, when the Sun crosses the celestial equator moving south and day and night are of equal length everywhere.

It marks the start of autumn in the northern hemisphere and of spring in the southern; its counterpart, the vernal equinox, falls around 20–21 March.