Which of the following rivers drain in the Arabian Sea?
(1) Periyar
(2) Bharathapuzha
(3) Mandovi
(4) Sharavati
Select the correct answer using the code given below:
(a) 1 only
(b) 1 and 2 only
(c) 2, 3 and 4 only
(d) 1, 2, 3 and 4
Ans: (d)
Explanation: Periyar is the second largest river which flows through Kerala and drains into Arabian sea. Bharathaphuzha - also known as Ponnani, is the longest river of Kerala. Goa has two important rivers - Mandovi and Juari. The Sharavati is another important river in Karnataka flowing towards the west. The Sharavati originates in Shimoga district of Karnataka and drains into the Arabian sea
Source: 11th NCERT- India: Physical Environment Page- 28.
2. Match List-I with List-II and select the correct answer using the code given below:
List-I Type of drought
List-II Definition
A. Meteorological Drought : 1. Characterised by low soil moisture that is necessary to support the crops, thereby resulting in crop failures.
B. Agricultural Drought : 2. Prolonged Period of inadequate rainfall marked with mal- distribution of the same over time and space
C. Hydrological Drought : 3. The productivity of a natural ecosystem fails due to shortage of water and as a consequence of ecological distress, damages are induced in the ecosystem
D. Ecological Drought : 4. Availability of Drought water in different storages and reservoirs like aquifers, lakes, reservoirs, etc. falls below what the precipitation can replenish
Codes
A B C D
(a) 3 2 4 1
(b) 4 1 2 3
(c) 2 1 4 3
(d) 1 2 3 4
Ans: (c)
Explanation:
Meteorological Drought: It is a situation when there is a prolonged period of inadequate rainfall marked with mal-distribution of the same over time and space.
Agricultural Drought: It is also known as soil moisture drought, characterised by low soil moisture that is necessary to support the crops, thereby resulting in crop failures. Moreover, if an area has more than 30% of its gross cropped area under irrigation, the area is excluded from the drought-prone category.
Hydrological Drought: It results when the availability of water in different storages and reservoirs like aquifers, lakes, reservoirs, etc. falls below what the precipitation can replenish.
Ecological Drought: When the productivity of a natural ecosystem fails due to shortage of water and as a consequence of ecological distress, damages are induced in the ecosystem.
Source-11th NCERT- India: Physical Environment - Page- 88, 90.
3. Which of the following initial conditions are needed for the generation of tropical cyclones?
(1) Large and continuous supply of warm and moist air that can release enormous latent heat.
(2) Strong Coriolis force that can prevent filling of low pressure at the centre.
(3) Unstable condition through the troposphere that creates local disturbances around which a cyclone develops.
(4) Presence of strong vertical winds.
Select the correct answer using the code given below:
(a) 3 only
(b) 1 and 2 only
(c) 1, 2 and 3 only
(d) 1, 2, 3 and 4
Ans: (c)
Explanation: A tropical cyclone or hurricane is like a heat engine that is energised by the release of latent heat on account of the condensation of moisture that the wind gathers after moving over the oceans and seas. Coriolis force is necessary for creation of cyclones.
Coriolis force makes cyclone swirl clockwise in the Southern hemisphere and counter-clockwise in the Northern Hemisphere. Absence of coriolis force near the equator prohibits the formation of tropical cyclone between 0°and 5° latitude.
Absence of strong vertical winds wedge is necessary as they disturb the vertical transport of latent heat. Tropical cyclone dissipates when heat source is taken away. They dissipate on reaching land.
Source- 11th NCERT- India: Physical Environment - Page- 84.
4. Every year, you visit your village for few days during summer time. Last year during such visit, you were informed by the farmers of your village that the ground water table has gone down drastically.
After doing some field study, you concluded that during Kharif season, majority of farmers were cultivating sugarcane (by using bore well irrigation) in place of other more suitable crops as per the local agro-climatic conditions.
You know that your village receives light rainfall from monsoon. It has black soil and is blessed with ample sunshine. Throughout the year, temperature is usually high with around 200 frost free days.
To address the issue of falling ground water table, in your opinion which among the following crops should be cultivated by the farmers of your village during Kharif season?
(a) Wheat
(b) Maize
(c) Coffee
(d) Cotton
Ans: (d) Explanation:
Sugarcane is a water-guzzling crop which is cultivated during Kharif season. Generally, range of tax incentives and subsidies from government encourage the farmers to go for only sugarcane cultivation while ignoring sustainable agriculture practices. For a location which has black soil, ample sunshine, receives light rainfall from monsoon and where temperature is usually high with around 200 frost free days; other more suitable crop for cultivation will be cotton. Such climatic conditions are the basic requirement for high production of cotton crop. Wheat and Maize are Rabi crops whereas Cotton is a Kharif crop.
Source: Geography NCERT – Class VIII – Page no 45 and Class Notes
5. From the outer space, the earth appears blue because
(a) Scattering of sunlight gives blue colour to the sky
(b) In space, only blue colour can be captured by human eye or telescope
(c) Earth's two-third surface is covered by water
(d) None of the above
Ans: (c)
Explanation:
From the outer space, the earth appears blue because its two-thirds surface is covered by water. It is, therefore, called a blue planet. The deepest ocean depths appear as deep, dark blue because all the other wavelengths get absorbed, while the deepest blues have the highest probability of getting reflected and re-emitted back out into the Universe.
Source: NCERT - Class VI - Social Science (Page - 5).