Daily Static MCQs Quiz for UPSC, IAS, UPPSC/UPPCS, MPPSC. BPSC, RPSC & All State PSC Exams
Subject : Geography
1. Consider the following statements regarding Mid-Oceanic Ridges:
1. Mid-oceanic ridge is an underwater mountain range, formed
by plate tectonics.
2. The mid-ocean ridges of the world are connected and form a single global
mid-oceanic ridge system that is part of every ocean.
3. They are characterised by a central rift system at the crest which is a zone
of volcanic activity.
How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (C)
Explanation: A mid-ocean ridge or mid-oceanic ridge is an underwater mountain range, formed by plate tectonics. This uplifting of the ocean floor occurs when convection currents rise in the mantle beneath the oceanic crust and create magma where two tectonic plates meet at a divergent boundary. The mid-ocean ridges of the world are connected and form a single global mid-oceanic ridge system that is part of every ocean, making the mid-oceanic ridge system the longest mountain range in the world, with a total length of about 60,000 km. It is characterised by a central rift system at the crest, a fractionated plateau and flank zone all along its length. The rift system at the crest is the zone of intense volcanic activity. Hence, all statements are correct.
2. Consider the following statements:
1. The temperature starts increasing with the increase in
altitude in Mesosphere.
2. The temperature starts decreasing with the increase in altitude in
ionosphere.
Which of the above statements is/are correct?
(a) 1 only
(b) 2 only
(c) Both 1 and 2
(d) Neither 1 nor 2
Answer: (D)
Explanation:
- The mesosphere lies above the stratosphere, which extends up to a height of 80 km. In this layer, temperature starts decreasing with the increase in altitude and reaches up to minus 100°C at the height of 80 km.
- The ionosphere is located between 80 and 400 km above the mesopause. It contains electrically charged particles known as ions, and hence, it is known as ionosphere. Temperature here starts increasing with height.
Hence, both statements are incorrect.
3. The Red Sea is one of the saltiest bodies of water in the world. This is due to:
1. High evaporation and low precipitation
2. Low discharge from fresh water bodies.
3. Limited connection with other open Oceans with lower salinity such as the
Indian Ocean.
How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (C)
Explanation: The Red Sea is one of the saltiest bodies of water in the world, owing to high evaporation and low precipitation; no significant rivers or streams drain into the sea, and its southern connection to the Gulf of Aden, an arm of the Indian Ocean, is narrow. Its salinity ranges from between ~36 ‰ in the southern part and 41 ‰ in the northern part around the Gulf of Suez, with an average of 40 ‰. Hence, all statements are correct.
4. Consider the following statements regarding Saline soils:
1. Saline soils are also known as Urvara Soils.
2. They have more salts, largely because of dry climate and poor drainage.
3. They occur in arid and semi-arid regions, and in waterlogged and swampy
areas.
How many of the above statements are correct?
(a) Only one
(b) Only two
(c) All three
(d) None
Answer: (B)
Explanation: Saline soils are also known as Usara soils. Saline soils contain a larger proportion of sodium, potassium and magnesium, and thus, they are infertile, and do not support any vegetative growth. They have more salts, largely because of dry climate and poor drainage. They occur in arid and semi-arid regions, and in waterlogged and swampy areas. Hence, statement 1 is incorrect.
5. Most volcanoes and earthquakes in the world are located at:
(a) Littoral zones of major oceans
(b) Within the plates
(c) Plate margins
(d) The inter-junction of high mountain stretches along the continental belts
Answer: (C)
Explanation: Plate margins witness several plate collisions, sliding, transformation etc that result into volcanism or earthquakes. Most of them are found in the Ring of Fire. Some earthquakes also occur within the plates but not as frequently as on the plate margins. Hence, option (c) is correct.
