CTET 2023 Previous Year GK Questions with Answers

The correct answer is B, Gravitational force and Normal force. A block lying quietly on a table is in equilibrium, so the forces on it must add up to zero, but that does not mean there are no forces at all. The Earth pulls the block down with its weight, mg. The table pushes back on it with an equal and opposite normal reaction, acting perpendicular to the surface, and these two balance each other. Friction is a force that appears only when there is motion along the surface or a tendency towards such motion; nothing is pushing the block sideways here, so no friction acts. This is Newton's first law in a familiar everyday form. Option A is wrong because gravity alone would make the block accelerate downward through the table. Option C is wrong because static friction needs an applied horizontal force that the block is resisting. Option D is wrong because sliding friction acts only while a body is actually sliding over a surface. Exam tip: on a body at rest with no horizontal push, only weight and normal reaction act, and friction is zero.

The correct answer is C, Mehrgarh. Mehrgarh, on the Bolan river in the Kachi plain of Baluchistan, is the earliest known farming village in the Indian subcontinent, occupied from about 7000 BCE. Its people were among the first in the region to grow wheat and barley and to rear sheep, goats and cattle, and the site records the long shift from hunting and gathering to settled village life. Archaeologists have found mud-brick houses, storage pits, burials with goods placed beside the dead, and some of the earliest evidence anywhere of cotton and of drilled teeth. Mehrgarh is treated as the forerunner of the Harappan civilisation. Option A is wrong because Hallur, in Karnataka, is a southern neolithic and megalithic site known for early iron. Option B is wrong because Chiraud, or Chirand, in Bihar is a neolithic site much later than Mehrgarh and famous for bone tools. Option D is wrong because Burzahom, in Kashmir, is known for pit dwellings and is also later. Exam tip: Mehrgarh of about 7000 BCE is the earliest village with wheat and barley, Burzahom has pit houses and Chirand has bone tools.

The correct answer is D, Brazil – Campos. Campos are the tropical grasslands of the Brazilian Highlands, so this is the only pair in the list that names a tropical grassland. Grasslands are grouped by the climate in which they grow. Tropical grasslands lie near the equator, have a hot climate with a clear wet and dry season, and carry tall coarse grass with scattered trees: the Savanna of Africa, the Llanos of Venezuela and the Campos of Brazil. Temperate grasslands lie in the middle latitudes, have cold winters and shorter grass, and are the world's great wheat and cattle lands. A is wrong because the Steppe of Central Asia is a temperate grassland. B is wrong because the Veld of South Africa is also temperate, spread over a high plateau. C is wrong because the Pampas of Argentina is the temperate grassland famous for wheat farming and cattle ranching. Every pair here names its region correctly; only Campos is tropical. Exam tip: tropical – Savanna, Llanos, Campos; temperate – Steppe, Prairies, Pampas, Veld, Downs.

The correct answer is A, (a)-(iv), (b)-(i), (c)-(ii), (d)-(iii). Marble is a metamorphic rock, formed when limestone is changed deep inside the earth by great heat and pressure; the Taj Mahal is built of it. Sandstone is a sedimentary rock, made of sand grains carried by wind or water and pressed together in layers over long periods, and it is the red stone of Fatehpur Sikri. Coal is counted as a fossil fuel, formed from plant remains buried in swamps millions of years ago and slowly changed by heat and pressure. Granite is an igneous rock, formed when molten magma cools and hardens below the surface, which gives it a coarse, grainy look and great hardness. B, C and D are wrong because each swaps at least two of these pairs, most often putting granite with sedimentary rocks or marble with igneous rocks. Exam tip: limestone becomes marble, magma gives granite, sand gives sandstone.

The correct answer is C, increase in area of contact reduces pressure exerted. Pressure is the force acting on unit area, that is P equals F divided by A, so for the same force a larger area of contact means smaller pressure. The weight of the bag stays exactly the same whether the strap is thin or wide, but a wide strap spreads that weight over more of the shoulder, so the shoulder feels less pressure and the strap does not cut into the skin. The same idea explains why school bags, seat belts and the wide tyres of a tractor are made broad. A is wrong because it states the relation upside down, since pressure falls when area rises. B and D are wrong because the force is simply the weight of the load and the width of the strap cannot change it; only the pressure changes. Exam tip: P equals F divided by A, so broad straps and flat feet reduce pressure while sharp knives and pointed nails increase it.

The correct answer is D, the statement that atmospheric pressure is negligible. Atmospheric pressure at sea level is about 1.013 into 10 to the power 5 pascal, which presses with roughly the weight of one kilogram on every square centimetre of our body, so it is very large and not negligible at all. We do not feel it because the pressure of the blood and other fluids inside the body pushes outward with the same force, and the two balance. A is a correct statement because pressure is force divided by area, so the same force on a smaller area gives more pressure, which is why knives are sharpened and nails are pointed. B is correct because a liquid presses in every direction, on the bottom as well as on the side walls, and the push grows with depth. C is correct because the column of air above us has weight and therefore presses on us. Exam tip: P equals force divided by area; atmospheric pressure at sea level is about 1.013 into 10 to the power 5 pascal.

The correct answer is C, (A) and (B). India does not keep separate sets of courts for central and state laws; it has one single pyramid, with the Supreme Court at the top, the High Courts below it and the district and subordinate courts at the base. Integration shows itself in exactly two ways, and both are named in statements (A) and (B): a ruling of a higher court binds every court below it, and a party unhappy with a lower court's order can carry the case upward in appeal. Statement (C) is untrue, because the Supreme Court is the highest court of the land and its powers are wider than a High Court's. Statement (D) is a general remark about the importance of the judiciary and says nothing about integration. A and D are therefore wrong because each of them includes (C), and B is wrong because it rests on (D). Exam tip: integrated judiciary means one hierarchy, appeals move up, and higher court rulings bind the courts below.

The correct answer is D, equal to its weight. A floating body is at rest, so the upward buoyant force must exactly balance the downward weight of the object. By Archimedes' principle the buoyant force equals the weight of the liquid displaced, so a floating object always displaces liquid weighing as much as the object itself. Here only half the volume is inside the liquid, which tells us that half the object's volume of that liquid weighs as much as the whole object, so the object's density is half the density of the liquid. How much of the body stays under the surface depends on this density ratio, not on the size of the buoyant force. A is wrong because a liquid always pushes up on a body dipped in it. B is wrong because a smaller upward force would let the object sink further. C is wrong because a larger upward force would push the object up until less of it stayed submerged. Exam tip: floating means buoyant force = weight; fraction submerged = density of body ÷ density of liquid.

The correct answer is A, Tin and copper. Bronze is made by melting copper and tin together, with copper as the main metal. It is harder than pure copper and does not corrode easily, so it has been used for statues, bells, medals and utensils for thousands of years. The Harappans cast the famous bronze figure of the 'dancing girl', and the Chola rulers of south India are known for their bronze idols such as Nataraja. An alloy is a mixture of a metal with other metals or with a non-metal, made to improve qualities like hardness, strength and resistance to rust. B is wrong because copper and zinc make brass, not bronze. C is wrong because aluminium and zinc do not make bronze; alloys of aluminium such as duralumin are used in aircraft. D is wrong because zinc and tin without copper do not form bronze. Exam tip: bronze, copper plus tin; brass, copper plus zinc; steel, iron plus carbon; stainless steel adds chromium and nickel.

The correct answer is B, Thyroid, Adrenal glands, Pituitary. The pituitary gland sends out hormones that order the thyroid and the adrenal glands to release their own hormones. The pituitary is a pea-sized gland attached to the base of the brain, and it is called the master gland because it controls several other endocrine glands. For example, it releases a thyroid-stimulating hormone that makes the thyroid produce thyroxine, and another hormone that makes the adrenal glands release theirs. NCERT's Class 8 science book notes that glands such as the thyroid and the adrenals secrete hormones on receiving a message from the pituitary. A is wrong because the pancreas releases insulin in response to blood sugar, and the thyroid does not command the other two. C is wrong because the testes and ovaries take their orders from the pituitary, not from the thyroid. D is wrong because the pituitary gives orders; it does not wait for orders from the thyroid. Exam tip: pituitary, master gland; thyroid, thyroxine; adrenal, adrenaline; pancreas, insulin.

The correct answer is A, Glass powder and red phosphorus. The rough strip of a safety matchbox is coated with powdered glass and a little red phosphorus, while the head of the matchstick carries antimony trisulphide and potassium chlorate. When the match is struck, friction turns some red phosphorus into white phosphorus. This reacts at once with the potassium chlorate in the head and produces enough heat to set the antimony trisulphide burning. Keeping the phosphorus on the box and the other chemicals on the stick is what makes the match safe. NCERT's Class 8 science book adds that early matches used white phosphorus, which proved dangerous for the workers who made them and for users. B is wrong because white phosphorus is not used on the rubbing surface of a safety match. C is wrong because magnesium is not part of the striking strip. D is wrong because neither potassium nor white phosphorus is found on the strip. Exam tip: box strip, red phosphorus plus glass powder; match head, antimony trisulphide plus potassium chlorate.

The correct answer is D, A, B and C. These three provisions keep judges free from pressure by the other organs of government, while the oath given by the President is only a formality. NCERT's Class 8 civics book explains that the legislature and the executive cannot interfere in the work of the judiciary, and judges are not answerable to them. Judges of the Supreme Court serve until 65 and those of High Courts until 62, and they can be removed only through a special process of impeachment, so their tenure is secure. Article 121 bars Parliament from discussing the conduct of a judge, except when a motion for removal is being considered. Statement D is a fact, but a ceremony of oath does not make judges independent. Option A is wrong because it adds statement D and drops C. Option B is wrong because it drops statement B, the fixed tenure. Option C is wrong because it adds statement D, which is not a safeguard. Exam tip: independence means appointment without the legislature, secure tenure, salaries charged on the Consolidated Fund and no debate on a judge's conduct.

The correct answer is C, Anti-slavery activists of American Civil War. Phule saw the condition of India's 'lower' castes as a form of slavery, so he dedicated his book to the Americans who had fought to free slaves. The book is Gulamgiri, which means slavery, published in 1873. Eight years earlier, in 1865, the American Civil War had ended with slavery abolished in the United States. By this dedication Phule linked the struggle against racial slavery in America with the struggle against caste in India. In the same year, 1873, he founded the Satyashodhak Samaj to work for caste equality. A is wrong because the book was not dedicated to India's anti-colonial nationalists. B is wrong because the Bhakti saints were poets of an earlier age, not the people Phule honoured in this book. D is wrong because the Brahmo Samaj reformers of Bengal were not the ones he dedicated it to. Exam tip: Gulamgiri (1873) and Satyashodhak Samaj (1873), both by Jyotirao Phule.

The correct answer is B, Article 21. Article 21 protects life and personal liberty, and the Supreme Court reads 'life' as a life with dignity, not mere survival. Over the years the Court has placed many rights inside it: the right to food, the right to a clean environment with pollution-free water and air, the right to shelter and livelihood, and the right to privacy. In the Puttaswamy case of 2017 a nine-judge bench declared privacy a fundamental right under Article 21. Article 21A, added in 2002, gives children aged 6 to 14 the right to free and compulsory education. A is wrong because Article 19 gives freedoms such as speech, assembly and movement. C is wrong because Article 14 guarantees equality before the law and equal protection of the laws. D is wrong because Article 20 protects a person against certain punishments, such as being punished twice for the same offence. Exam tip: Article 21, life and liberty; 21A, education; 14, equality; 19, freedoms.

The correct answer is A, Waterways. Water transport needs no track or road to be built, and a ship or barge can carry huge loads on little fuel, so the cost per tonne is the lowest. That is why coal, iron ore, food grains, cement and containers travel across oceans and along rivers and canals in ships and barges. NCERT's geography textbook calls waterways the cheapest way of carrying heavy and bulky goods over long distances. India's inland waterways, such as National Waterway 1 on the Ganga from Prayagraj to Haldia, use the same idea. The price paid for the low cost is slow speed. B is wrong because railways are cheaper than roads for bulk goods but still cost more than waterways. C is wrong because airways are the fastest but the costliest, and suit light and valuable goods. D is wrong because roadways are best for short distances and door-to-door delivery. Exam tip: cheapest, waterways; fastest, airways; door-to-door, roadways.

The correct answer is B, 3 p.m. Places east of Greenwich are ahead in time, and every degree of longitude adds 4 minutes. The Earth turns through 360° in 24 hours, so it covers 15° in one hour, or 1° in 4 minutes. For 45° East the difference is 45 × 4 = 180 minutes, which is 3 hours. Because the place lies east of Greenwich, we add these 3 hours to 12 noon and get 3 p.m. The short rule is 'East gains, West loses'. A is wrong because 9 a.m. comes from subtracting 3 hours, which would be right only for 45° West. C is wrong because 10 a.m. would be the time at a place 30° West of Greenwich. D is wrong because 2 p.m. would be the time at a place only 30° East of Greenwich. Exam tip: 1° = 4 minutes and 15° = 1 hour; add time going east, subtract going west. India's Standard Meridian at 82½° E is 5 hours 30 minutes ahead of Greenwich.