MCQ FOR UPSC AND KPSC PRELIMS 3

Question

Consider the following statements about the Bailey Bridge:

1. The Bailey Bridge is a type of modular bridge, assembled quickly with pre-built parts and minimal construction work.
2. It was invented by an American civil engineer during World War II.
3. Bailey bridges are ideal for disaster relief and military use because they do not require heavy installation equipment and can be transported in small trucks.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 2 is incorrect because the Bailey Bridge was invented by Donald Coleman Bailey, an English civil engineer, not an American.

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Consider the following statements about the construction of Bailey Bridges:

1. Bailey bridges use light steel panels linked through pins to create guardrails.
2. The beams that form the deck of the bridge are placed directly on the ground.
3. The parts of a Bailey bridge are designed to lock together for enhanced stability and can be extended.

Which of the above statements is/are correct?

a) 1 and 3 only
b) 2 and 3 only
c) 1 and 2 only
d) 1, 2, and 3

Answer: a) 1 and 3 only
Explanation: Statement 2 is incorrect because the beams form the deck of the bridge on top of the guardrails, not directly on the ground.

Consider the following statements about the Ol Doinyo Lengai Volcano:

1. Ol Doinyo Lengai is located in northern Tanzania and is known as the "Mountain of God" by the local Maasai people.
2. It is the only volcano on Earth that actively erupts carbonatite magma, which is highly rich in silica.
3. The volcano is part of the East African Rift System and has an elevation of 9,442 feet.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 2 is incorrect because Ol Doinyo Lengai's carbonatite magma is poor in silica, not rich in it.

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Consider the following statements about Ol Doinyo Lengai Volcano:

1. Ol Doinyo Lengai has more than one active center, with most recent eruptions occurring from its northern crater.
2. The lavas of Ol Doinyo Lengai are extremely alkaline, containing high amounts of sodium and potassium, making them resemble washing soda.
3. The volcano's magma is unique because it contains high levels of silica and low levels of alkali elements like sodium and calcium.

Which of the above statements is/are correct?

a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3

Answer: a) 1 and 2 only
Explanation: Statement 3 is incorrect because the magma is poor in silica and rich in alkali elements like sodium and calcium.

Consider the following statements about the Standardised Precipitation Index (SPI):

1. The SPI is used to estimate both wet and dry conditions based on long-term precipitation data for a specific location.
2. A positive SPI value indicates drought conditions, while a negative value indicates wet conditions.
3. The SPI can be calculated for timescales ranging from 1 month to 72 months.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 2 is incorrect because a positive SPI value indicates wet conditions, and a negative SPI value indicates drought.

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Consider the following statements about the Standardised Precipitation Index (SPI):

1. The SPI is based on long-term precipitation data, preferably over a period longer than 30 years.
2. The SPI becomes more negative as drought conditions worsen and more positive as wet conditions intensify.
3. The SPI only calculates short-term timescales, such as 1 to 12 months.

Which of the above statements is/are correct?

a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3

Answer: a) 1 and 2 only
Explanation: Statement 3 is incorrect because the SPI can calculate for a range of timescales, including both short-term and long-term periods, from 1 month to 72 months.

Answer 1

Consider the following statements about the Second Thomas Shoal:

1. The Second Thomas Shoal is located in the Spratly Islands in the South China Sea.
2. The Philippines maintains an outpost on the Second Thomas Shoal called the BRP Sierra Madre.
3. The Second Thomas Shoal is located within 500 nautical miles of the Philippine island of Palawan.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 3 is incorrect because the Second Thomas Shoal lies about 108 nautical miles (200 km) from the Philippine island of Palawan, not 500 nautical miles.

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Consider the following statements regarding the South China Sea disputes:

1. China claims sovereignty over most of the South China Sea, including the Second Thomas Shoal, based on the Nine-dash line.
2. The Second Thomas Shoal is located within the exclusive economic zones (EEZs) of multiple Southeast Asian countries.
3. Vietnam is the only country that disputes China’s claims in the South China Sea.

Which of the above statements is/are correct?

a) 1 and 2 only
b) 1 and 3 only
c) 2 and 3 only
d) 1, 2, and 3

Answer: a) 1 and 2 only
Explanation: Statement 3 is incorrect because several countries, including the Philippines, Malaysia, Brunei, and Indonesia, dispute China’s claims in the South China Sea, not just Vietnam.

Consider the following statements about Rogue Waves:

1. Rogue waves are unusually large ocean surface waves that can be more than twice the size of nearby waves.
2. Rogue waves are always predictable and move in the same direction as prevailing wind and wave motion.
3. Rogue waves can occur both in the open ocean and near-shore areas, causing damage to coastal structures and small fishing boats.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 2 is incorrect because rogue waves are unpredictable and may move in different directions, including against the prevailing wind and wave motion.

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Consider the following statements about the characteristics and formation of Rogue Waves:

1. Rogue waves are formed due to the coincidental stacking of multiple wind-driven wave crests.
2. They have been observed only in the Pacific Ocean.
3. Rogue waves can be as tall as twice the size of nearby waves and resemble "walls of water."

Which of the above statements is/are correct?

a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3

Answer: c) 1 and 3 only
Explanation: Statement 2 is incorrect because rogue waves have been observed in many oceans, including the Pacific, Atlantic, Indian Ocean, and the Mediterranean Sea.

Answer 2

Consider the following statements about Rock Varnish Layers in Ladakh:

1. Rock varnish is a dark brown to black coating that forms on rock surfaces, mainly in arid and semiarid regions.
2. The presence of magnetofossils in Ladakh’s rock varnish layers suggests biotic sources for the magnetic minerals found there.
3. Magnetofossils are the remains of magnetotactic bacteria, which contain fossilised radioactive particles.

How many of the above statements is/are correct?

a) only one
b) only two
c) all three
d) none

Answer: b) only two
Explanation: Statement 3 is incorrect because magnetofossils contain magnetic minerals, not radioactive particles.

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Consider the following statements about the findings related to rock varnish in Ladakh:

1. The rock varnish in Ladakh shows high concentrations of oxidized manganese and organic signatures.
2. Ladakh’s rock varnish layers may serve as a Martian analogue due to the presence of biotic magnetic minerals.
3. Magnetofossils in Ladakh are unique to this region and have not been found elsewhere.

Which of the above statements is/are correct?

a) 1 and 2 only
b) 2 and 3 only
c) 1 and 3 only
d) 1, 2, and 3

Answer: a) 1 and 2 only
Explanation: Statement 3 is incorrect because magnetofossils are not unique to Ladakh and have been found in other regions as well.