Previous Year UPSC Questions

Explanation

A comet is a small celestial body composed of ice, dust, and rocky material that orbits the Sun in an elliptical path. When it gets close to the Sun, the heat causes its icy nucleus to vaporize, forming a glowing coma.

Option (c) is correct: The tail of a comet is directed away from the Sun due to the solar wind and radiation pressure exerted by the Sun. The Sun emits charged particles (mainly electrons and protons) that interact with the comet’s nucleus and coma, pushing gas and dust away. This creates a glowing tail that always points opposite the Sun, regardless of the comet’s orientation. The tail’s direction can change as the comet moves, influenced by factors like solar wind intensity, the coma’s shape, and the Sun’s magnetic field.

Explanation

Butler Committee Report (1927) focused on the relationship between the Indian states and the British Paramount Power. It studied the status and governance of princely states under British rule. Hurtog Committee Report (1929) studied the growth of education in India and its future potential. The committee also emphasized on the role of higher education in producing trained administrative personnel for the British government. Hunter Inquiry Committee Report (1920) investigated the Jallianwala Bagh massacre and its aftermath. The report was criticized for being a whitewashed account of the massacre, as it did not hold Dyer accountable in a meaningful way. The Muddiman Committee Report (1924) examined the working of the dyarchy introduced under the Montagu-Chelmsford Reforms (1919). The committee’s report found that the dyarchy system was not working effectively due to several reasons, such as the lack of real power in the hands of Indian ministers, bureaucratic resistance, etc.

Explanation

A is matched with 5: Chennai (formerly Madras) is located at approximately 13°N latitude, while Kolkata (formerly Calcutta) is located at around 22.5°N latitude. The closer a location is to the equator, the higher the average temperature due to more direct sunlight throughout the year. This is why Chennai is warmer than Kolkata, as it is situated closer to the equator. B is matched with 2: Snowfall in the Himalayas is primarily due to high altitude, rather than latitude. The Himalayas have several peaks above 6,000 meters (20,000 feet), where temperatures remain below freezing for most of the year. C is matched with 4:West Bengal is closer to the Bay of Bengal, which brings heavy monsoon rains during June-September. As you move inland towards Punjab, the moisture-laden winds lose their strength and moisture due to the continental effect (distance from the sea). D is matched with 3: During winter (December-February), the Western Disturbances (low-pressure systems from the Mediterranean region) bring rainfall to northern India, especially in Punjab, Haryana, and western Uttar Pradesh.

Explanation

A is matched with 3: The Deccan Traps are one of the largest volcanic provinces in the world, formed due to massive volcanic eruptions during the late Cretaceous and early Eocene periods (about 66 million years ago). These lava flows cover a vast part of western and central India. B is matched with 1: The Western Ghats, that include Sahyadri Hills, are part of the Late Cenozoic formations, meaning they formed relatively recently in geological history. These mountains are the result of faulting and uplift processes. C is matched with 2: The Aravalli Range is one of the oldest mountain ranges in the world, dating back to the Pre-Cambrian era. It is heavily eroded and was once part of a much larger mountain system. D is matched with 5: The river valleys of the Narmada and Tapi belong to the Pleistocene era (about 2.5 million to 11,700 years ago). They have alluvial deposits from recent geological periods due to sedimentation from river action.

Explanation

The 18°C January isotherm is used as the dividing line between the tropical and subtropical zones in India. This isotherm runs roughly along the Tropic of Cancer (23.5°N latitude) and helps distinguish the warmer tropical climate of southern India from the relatively cooler subtropical climate of northern India. Areas south of the 18°C isotherm (covering most of Peninsular India) experience tropical climate with higher temperatures, minimal winter, and a distinct monsoon pattern. Areas north of the 18°C isotherm (including northern states like Punjab, Haryana, and parts of Uttar Pradesh) fall under the subtropical zone, experiencing cooler winters and greater temperature variations between seasons.

Explanation

The Alamatti Dam is constructed on the Krishna River in Karnataka. It is a part of the Upper Krishna Irrigation Project and is located in Bagalkot district. The dam plays a crucial role in irrigation, hydroelectric power generation, and water management in Karnataka. It is one of the largest reservoirs in South India and helps regulate the flow of the Krishna River.

Explanation

The Farakka Barrage was constructed across the Ganga River in West Bengal with the aim of diverting water to the Hooghly River to ensure that the Kolkata Port remains navigable. The Farakka Feeder Canal is responsible for carrying the diverted water into the Hooghly River. Canal Capacity: The canal has a designed carrying capacity of 40,000 cusecs, which is the amount of water it can carry per second. This is an important feature of the Farakka Barrage, as it ensures the flow of sufficient water into the Hooghly River to prevent silting and to support the navigation in Kolkata’s port.

Explanation

Pair (d) is correctly matched: Sundari is a type of mangrove tree that is found in the Sundarbans region of West Bengal. It is well known for its role in the coastal ecosystem of the Sundarbans and is the dominant species in the mangrove forest. Pairs (a), (b) and (c) are incorrectly matched:

Teak is predominantly found in Tamil Nadu, Karnataka, and Kerala, not in Jammu and Kashmir. Jammu and Kashmir is known for coniferous trees like Chir Pine and Fir. Deodar (Cedrus deodara) is primarily found in Himachal Pradesh, Jammu and Kashmir, and Uttarakhand, not in Madhya Pradesh. Madhya Pradesh has a variety of other trees like Sal and Saja. Sandalwood (Santalum album) is native to Karnataka, Tamil Nadu, and Andhra Pradesh. Kerala is not popularly known for sandalwood cultivation, although the tree may grow there in some areas.

Explanation

Fluorine is the most reactive halogen because:

Small Atomic Size: Fluorine has the smallest atomic radius among halogens, leading to a strong attraction for electrons. High Electronegativity: It is the most electronegative element in the periodic table, making it highly effective in gaining electrons. Low Bond Dissociation Energy: The F-F bond in molecular fluorine is weak due to electron repulsion between the two small atoms, which makes it highly reactive. Reactivity Trend in Halogens:

Fluorine > Chlorine > Bromine > Iodine

Explanation

A is matched with 3: The President of India takes an oath to "preserve, protect, and defend the Constitution" and uphold the Constitution of India, which corresponds to the oath of faith and allegiance to the Constitution. B is matched with 4: Judges of the Supreme Court swear to "discharge their duties without fear or favor" and uphold the Constitution and the law, aligning with the oath of upholding the Constitution and the law. C is matched with 2: Members of Parliament pledge to "bear true faith and allegiance to the Constitution of India," which corresponds to the oath of faith and allegiance to the Constitution. D is matched with 1: According to Article 75(4), ministers take an oath to uphold secrecy and faithfully discharge their duties.