Daily Quiz #13 UPSC Prelims Marathon – August 16, 2019

Explanation: Density of population is expressed as number of persons per unit area. It helps in getting a better understanding of the spatial distribution of population in relation to land. The density of population, is a crude measure of human and land relationship. To get a better insight into the human-land ratio in terms of pressure of population on total cultivable land, the physiological and the agricultural densities should be found out which are significant for a country like India having a large agricultural population.
Physiological density = total population / net cultivated area
Agricultural density = total agricultural population / net cultivable area
Agricultural population includes cultivators and agricultural labourers and their family members.
Agricultural density is the ratio between only the agricultural population and the total cultivated area. Therefore, the agricultural density is expressed in terms of agricultural population per unit of cultivated area. It has proved to be a useful index of man- land relationship in primarily an agrarian context.
Physiological density is a ratio between total population and total cultivable land. It is expressed in terms of persons/km2 of cultivable land. The correct picture of the human pressure on land is derived by physiological density. Thus, when compared with arithmetic density, physiological density is defined a method of calculating man-land ratio:
Population Density=(Total population)/(Net cultivable area)

Explanation: The Krishna River is one of the most important peninsular Rivers In India. It is one of the most extensive rivers in central-southern India. The river is almost 1,300 km (810 miles) long. On certain occasions, the Krishna River is denoted as Krishnaveni. The river functions as a source of irrigation water for Karnataka, Maharashtra, and Andhra Pradesh.
The Krishna River has its origin at Mahabaleswar in the vicinity of Jor village in the state of Maharashtra. The river ultimately pours into the Bay of Bengal at Hamasaladeevi in Andhra Pradesh, on the eastern shorelines of India.
Manjira is a tributary of Godavari River. Other major tributaries of the river are Indravati, Sabari River and Bindusara River

Explanation: Stalactite and Stalagmite are depositional landforms in a cave. A stalactite is an icicle-shaped formation that hangs from the ceiling of a cave, and is produced by precipitation of minerals from water dripping through the cave ceiling. Most stalactites have pointed tips.

A stalagmite is an upward-growing mound of mineral deposits that have precipitated from water dripping onto the floor of a cave. Most stalagmites have rounded or flattened tips.

There are many other types of mineral formations found in caves. For example, flowstones are deposits of minerals from water flowing over the floor or walls of a cave. As layers of flowstone become thicker, their shape becomes rounded. Well-defined crystals growing underwater in cave pools are known as pool spar.

Some deposits are named based on their appearance, such as a showerhead, which is a hollow cone-shaped formation, narrow above and broad below. Showerheads are generally only found in tropical caves. A conulite is a “splash cup” that forms when water dripping rapidly through the cave ceiling flings aside loose particles on the cave floor.

Explanation: Wind is one of the two dominant agents in hot deserts. The desert floors get heated up too much and too quickly because of being dry and barren. The heated floors heat up the air
directly above them and result in upward movements in the hot lighter air with turbulence, and any obstructions in its path sets up eddies, whirlwinds, updrafts and downdrafts.
Erosional landforms include Pediments, pediplains, playas and mushroom, table and pedestral roacks. The depositional landforms include dunes.
Landscape evolution in deserts is primarily concerned with the formation and extension of pediments. Gently inclined rocky floors close to the mountains at their foot with or without a thin cover of debris, are called pediments. Such rocky floors form through the erosion of mountain front through a combination of lateral erosion by streams and sheet flooding. Erosion starts along the steep margins of the landmass or the steep sides of the tectonically controlled steep incision features over the landmass. Once, pediments are formed with a steep wash slope followed by cliff or free face above it, the steep wash slope and free face retreat backwards. This method of erosion is termed as parallel retreat of slopes through backwasting. So, through parallel retreat of slopes, the pediments extend backwards at the expense of mountain front, and gradually, the mountain gets reduced leaving an inselberg which is a remnant of the mountain. That’s how the high relief in desert areas is reduced to low featureless plains called pediplains.
Playas
Plains are by far the most prominent landforms in the deserts. In basins with mountains and hills around and along, the drainage is towards the centre of the basin and due to gradual deposition of sediment from basin margins, a nearly level plain forms at the centre of the basin.