1. Consider the following statements:
(1) The rock equidistant on either side of the crest of mid-oceanic ridges are
similar in terms of period of formation.
(2) The continental rocks are generally older than that of oceanic crust.
Which of the statements given above is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Ans: (c) Explanation: The mapping of the ocean floor and paleo-magnetic studies of rocks from oceanic regions revealed the following facts: It was realised that all along the mid-oceanic ridges, volcanic eruptions are common, and they bring huge amounts of lava to the surface in this area. The rocks equidistant on either side of the crest of mid-oceanic ridges show remarkable similarities in terms of period of formation, chemical compositions and magnetic properties. Rocks closer to the mid-oceanic ridges have normal polarity and are the youngest. The age of the rocks increases as one moves away from the crest. Hence, statement 1 is correct. The ocean crust rocks are much younger than the continental rocks. The age of rocks in the oceanic crust is nowhere more than 200 million years old. Some of the continental rock formations are as old as 3,200 million years. Hence, statement 2 is correct. These facts and detailed analysis of magnetic properties of the rocks on either side of the mid-oceanic ridge led Harry Hess (1961) to propose his hypothesis, known as the “sea floor spreading”.
Source: NCERT- Class XI Fundamental of Physical Geography- Page no. 33.
2. You have decided to visit ‘Sundarban Tiger Reserve’. Select the correct sequence of unique forest types which you will encounter one by one during your journey towards Sundarban if you start at Kanyakumari:
(a) Tropical Deciduous > Tropical Thorn > Littoral and Swamp > Tropical Semi-evergreen
(b) Tropical Semi-evergreen > Tropical Deciduous > Tropical Thorn > Littoral and Swamp
(c) Tropical Semi-evergreen > Tropical Thorn > Tropical Deciduous > Littoral and Swamp
(d) Tropical Thorn > Tropical Deciduous > Littoral and Swamp > Tropical Semi- evergreen
Ans: (b)
Explanation: Tropical Semi-Evergreen Forests: These are found in the Western Ghats, Andaman and Nicobar Islands, and the Eastern Himalayas but in relatively less rainy areas of the region. Such forests have a mixture of the wet evergreen trees and the moist deciduous trees. Tropical Deciduous Forests: The largest area of the country’s forest land is occupied by Tropical deciduous forests. These forests are distributed in the areas where annual rainfall is usually low, ranging between 70 and 100 cm, such as U.P., and Bihar, Odisha, M.P. and large part of Indian peninsula. Tropical Thorn Forests: These include a variety of grasses and shrubs. They are found in semi arid areas like Rajasthan, Gujarat, etc. Such forests also grow on the leeside of the Western Ghats covering large areas of Maharashtra, Karnataka, Telangana, Andhra Pradesh and Tamil Nadu. Littoral & Swampy Forests: They include - Beach forests, tidal forests, mangrove forests and fresh water swamp forests.
Source: Geography NCERT India Physical – Class XI – Page no 58
3. Which of the following statements is/are correct about Agenda 21?
(1) It is a declaration signed by world leaders at UN Conference on Environment
and Development in 1892.
(2) It aims at achieving global sustainable development.
(3) One of the criticism of Agenda 21 is it did not encourage local agenda for
sustainable development.
Select the correct answer using the code given below:
(a) 2 only
(b) 1 and 2 only
(c) 2 and 3 only
(d) 1, 2 and 3
Ans: (a)
Explanation: Agenda 21 is a comprehensive plan of action to be taken globally, nationally and locally by organizations of the United Nations System, Governments, and Major Groups in every area in which human impacts the environment.
Statement 1 is incorrect as the conference was held in 1992 at UNCED at Rio De Janeiro, Brazil. Statement 2 is correct. It aims at combating poverty, environmental damage, diseases through global cooperation. Hence, addressing sustainable development. Statement 3 is incorrect. One of the high points of Agenda 21 is that it explicitly mentions for every local government to draw its own Agenda 21.
Source: NCERT class 10th, Page no- 3.
4. Consider the following pairs:
1. Bailadila hills : Bituminous Coal
2. Balaghat : Bauxite mines
3. Panchpatmali deposits : Mica
Which of the above pairs is/are correctly matched?
(a) 2 only
(b) 3 only
(c) 1, 2 and 3
(d) None of the above
Ans: (d)
Explanation: India is endowed with a rich variety of mineral resources due to its varied geological structure. Most of the metallic minerals in India occur in the peninsular plateau region in the old crystalline rocks. Bailadila hills of Chhattisgarh district are famous for very high-grade hematite ores. Balaghat mines of Madhya Pradesh produce 52% of India’s copper. Panchpatmali deposits in Koraput district are the most important deposits of Bauxite in Odisha which in turn is the largest bauxite producing state in the country. Also, over 97 per cent of coal reserves occur in the valleys of Damodar, Sone, Mahanadi and Godavari. Petroleum reserves are located in the sedimentary basins of Assam, Gujarat and Mumbai High i.e. off-shore region in the Arabian Sea.
Source: NCERT class 10th, page no 54-55.
5. Which of the following statements regarding drainage pattern is correct?
(a) A trellis pattern develops on a strongly jointed rocky terrain.
(b) In trellis pattern, tributaries join the main river at approximately right angles.
(c) A rectangular drainage pattern develops where hard and soft rocks exist
parallel to each other.
(d) In dendritic pattern, streams flow in different directions from a central dome.
Ans: (b)
Explanation: Drainage patterns are patterns formed by the streams, rivers, and lakes in a particular drainage basin. They are governed by the topography of the land, whether a particular region is dominated by hard or soft rocks, and the gradient of the land.
Rectangular drainage pattern develops on a strongly jointed rocky terrain. Statement c is incorrect. Trellis drainage pattern develops where hard and soft rocks exist parallel to each other. Statement d is incorrect. In radial pattern, streams flow in different directions from a central dome. Dendritic pattern is one in which river follows the slope of terrain. The streams and the river resemble the branches of a tree hence the name dendritic. Statement b is correct. In trellis pattern, tributaries join the main river at approximately right angles.
Source: NCERT class 9th, Page no- 18.