UPSC 2000 Prelims Questions with Answers

Explanation

The first sunrise of the new millennium (1 January 2000) in India was observed at the 92°30’ E meridian in Arunachal Pradesh, the country’s easternmost region. Located near the Myanmar border, this was the first point in India to receive sun-light as the millennium began. While countries like New Zealand saw it earlier due to their proximity to the International Date Line, within India, 92°30’ E, the nation’s easternmost meridian amongst the given options, marked the dawn of the new era, highlighting its significance as the first place in the country to witness sunrise.

Explanation

Statement 1 is correct: Tides play a significant role in both navigation and fishing activities. Tides help ships navigate shallow waters by increasing water depth during high tide. They also influence fishing, as certain fish species move with tidal currents, making them easier to catch.

Statement 2 is correct: High tides increase the water level in harbors, which is essential for larger ships to enter or leave safely. Without the rise in water levels brought about by tides, large ships might find it difficult to dock or leave the harbor, as they need sufficient water depth to avoid grounding.

Statement 3 is correct: The ebb and flow of tidal waters help to flush out silt, sand, and other debris from the harbor area. This natural process reduces the risk of siltation, ensuring that ports and harbors remain navigable by preventing the accumulation of sediments that could otherwise block ships.

Statement 4 is correct: Both Kandla Port (in Gujarat) and Diamond Harbour (near Kolkata) are tidal ports, meaning they are influenced by tidal movements. The activities at these ports depend on the high and low tide cycles for ships to dock and undock, as well as to ensure proper water levels for smooth navigation.

Explanation

Assertion (A) is true: The frequency of floods in the north Indian plains has indeed risen in recent decades. This can be attributed to a combination of factors:

Climate Change: With global warming, the frequency and intensity of rainfall events have increased. In many parts of India, especially in the north, monsoon rains have become more unpredictable, leading to sudden heavy downpours that overwhelm the drainage systems and flood the plains. Urbanization and Poor Drainage Systems: As more urban areas are developed, the natural landscape changes. Cities with poor drainage systems cannot handle heavy rainfall, leading to waterlogging and flooding. Deforestation: Deforestation, particularly in the catchment areas of rivers, reduces the land’s ability to absorb rainfall. The lack of tree cover and vegetation increases surface runoff, which can rapidly flow into rivers and cause them to overflow. River Management Issues: Rivers like the Ganges and Brahmaputra are heavily managed with embankments, dams, and other infrastructure. However, many of these structures have not been properly maintained, or they have been poorly designed, leading to insufficient control of water flow. This poor management has exacerbated the flood situation. Reason (R) is true: Over time, rivers in flood-prone regions like the Ganges, Brahmaputra, and their tributaries have experienced significant sediment deposition, which raises the riverbed and reduces the river’s depth. Several factors contribute to this:

Sediment Transport: Rivers like the Ganges and Brahmaputra carry a large amount of sediment, the continuous accumulation of sand, silt, and clay sediment raises the riverbed, gradually reducing the depth of the river valleys. This process is particularly noticeable in the north Indian plains, where large rivers meander and deposit substantial amounts of sediment. Shallow Riverbeds: As the riverbed rises due to sedimentation, the rivers become shallower and have less capacity to hold and carry water. When heavy rainfall occurs, rivers with reduced capacity cannot contain the additional water, causing them to overflow and flood the surrounding areas. Floodplains and Siltation: Floodplains are areas adjacent to rivers that are prone to flooding during high-water events. These floodplains naturally receive silt deposits from the river during floods, but when silt deposition becomes excessive, the height of the floodplain increases, reducing the storage capacity of the river. The increased frequency of floods (Assertion A) is directly related to the siltation or sediment buildup in the river valleys (Reason R).

Explanation

A rise in SENSEX indicates an overall increase in the stock prices of a group of 30 financially strong companies listed on the Bombay Stock Exchange (BSE). These companies are selected based on market capitalization, liquidity, and sectoral representation and are considered indicators of market performance. SENSEX movements reflect investor sentiment, economic conditions, corporate earnings, and global market trends. It does not mean that the prices of all companies listed on the BSE rise simultaneously. As per the Bombay Stock Exchange (BSE) reports, Sensex is widely used by investors and analysts to gauge India’s stock market trends and investment climate.

Explanation

Nichrome is an alloy of nickel and chromium, often used in heating elements due to its high resistance to heat and corrosion. It is ductile, allowing it to be drawn into wires for use in various applications. It is considered hard relative to other ductile materials, which is why it finds applications in industrial heating where both durability and flexibility are important. Options (a), (b) and (c) are incorrect:

Carborundum (silicon carbide) is very hard but not ductile; it is brittle. It is mainly used as an abrasive material. Cast iron is hard but brittle, and it cannot undergo significant deformation without breaking. While Tungsten is harder, it is less ductile compared to Nichrome in practical scenarios. Tungsten’s brittleness increases under certain conditions, making Nichrome a more balanced choice for being both hard and ductile.

Explanation

Aleutian Trench - North Pacific Ocean Located along the Aleutian Islands, Alaska, it is a subduction zone where the Pacific Plate sinks beneath the North American Plate. Kermadec Trench - South Pacific Ocean Found near New Zealand, it is one of the world’s deepest trenches, formed by the subduction of the Pacific Plate under the Indo-Australian Plate. Sunda Trench - Indian Ocean Also called the Java Trench, it lies off the coast of Sumatra, Indonesia, and is associated with frequent earthquakes and tsunamis. South Sandwich Trench - South Atlantic Ocean Located near the South Sandwich Islands, it is the deepest trench in the Atlantic Ocean, formed by the subduction of the South American Plate beneath the Scotia Plate.

Explanation

Statement 1 is correct: Hard water, rich in calcium and magnesium, can contribute to dietary intake of these minerals, but prolonged consumption may lead to kidney stones and urinary tract issues, particularly for susceptible individuals. Research indicates that high calcium levels can affect renal function.

Statement 2 is correct: When hard water is used with soap, it forms soap scum, which reduces lather and makes washing less effective. Scum leaves residue on clothes, making them feel rough and unclean. This can also increase detergent usage.

Statement 3 is correct: The minerals in hard water like calcium carbonate and magnesium salts, form scale in boilers and pipes, reducing thermal efficiency and leading to energy wastage and equipment failure.

Statement 4 is correct: Continuous irrigation with hard water results in soil salinization, decreasing permeability and crop yield. Excess minerals like calcium and magnesium hinder plant nutrient absorption due to reduced soil’s permeability. Directions: The following two Items consist of statements. One labeled as the ‘Assertion (A)’ and the other as ‘Reason (R)’. You have to answer these items using the code given below: (1999)

Explanation

Central Institute of Higher Tibetan Studies - Varanasi A premier institute for Tibetan studies, Buddhist philosophy, and ancient Indian wisdom, located in Uttar Pradesh. Indira Gandhi Institute of Development Research - Mumbai A research institution focusing on economic development and policy studies, located in Maharashtra. National Institute of Mental Health and Neuro-Sciences (NIMHANS) - Bangalore A leading center for mental health and neuroscience research, based in Karnataka. Central Institute of English and Foreign Languages (now EFLU) - Hyderabad A prestigious university specializing in English and foreign language studies, situated in Telangana.

Explanation

Mineral Oil - Venezuela Venezuela has some of the largest oil reserves in the world, primarily in the Orinoco Belt. Copper - Zambia Zambia is a major producer of copper, particularly from the Copperbelt region, which contributes significantly to its economy. Manganese - Gabon Gabon is one of the world’s top manganese producers, with significant deposits in the Moanda region. Bauxite - Guyana Guyana is a key bauxite-producing country, with large deposits found in Linden and Berbice.

Explanation

M/s Gowthami Solvents Oil Ltd, Andhra Pradesh - Rice husk This plant utilizes rice husk, an agricultural waste product, as a biomass fuel for power generation. M/s K.M. Sugar Mills, Uttar Pradesh - Distillery spent wash The sugar mill uses distillery spent wash, a byproduct of sugar and ethanol production, for energy generation. M/s Satia Paper Mills, Punjab - Black liquor A paper mill that generates power from black liquor, a byproduct of the pulp and paper industry. M/s Al Kabeer Exports Ltd, Andhra Pradesh - Slaughterhouse waste This plant generates biogas from slaughterhouse waste, which is used for energy production.