Insights Static Quiz -285, 2019–Geography

Solution: c)

About 98 per cent of the total crust of the earth is composed of eight elements like oxygen, silicon, aluminium, iron, calcium, sodium, potassium and magnesium, and the rest is constituted by titanium, hydrogen, phosphorous, manganese, sulphur, carbon, nickel and other elements.

The Major Elements of the Earth’s Crust

Sl. No.                                                  Elements By Weight(%)

1. Oxygen                                       46.60
2. Silicon                                        27.72
3. Aluminium                                8.13
4. Iron 5.00
5. Calcium                                      3.63
6. Sodium                                       2.83
7. Potassium                                  2.59
8. Magnesium                                2.09
9. Others                                         1.41

Solution: b)

Divergent Boundaries: Where new crust is generated as the plates pull away from each other. The sites where the plates move away from each other are called spreading sites. The best-known example of divergent boundaries is the Mid-Atlantic Ridge. At this, the American Plate(s) is/are separated from the Eurasian and African Plates.

Solution: c)

The insolation received at the surface varies from about 320 Watt/m2 in the tropics to about 70 Watt/m2 in the poles. Maximum insolation is received over the subtropical deserts, where the cloudiness is the least. Equator receives comparatively less insolation than the tropics. Generally, at the same latitude the insolation is more over the continent than over the oceans. In winter, the middle and higher latitudes receive less radiation than in summer.

Solution: c)

Tarapur – Maharashtra

Narora – Uttar Pradesh

Solution: c)

• Statement 1 – Any land, which is left without cultivation for one or less than one agricultural year is known as Current Fallow.
• Statement 2 – Barren hilly terrains, desert lands, ravines, etc. normally are not suitable for cultivation, hence, they are known as Barrenand Wastelands.
• Statement 3 – Any land, which is left fallow (uncultivated) for more than five years is categorized as Culturable Wasteland.
• Statement 4 – The physical extent of the land on which crops are sown and harvested is known as Net Sown Area.