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RRB JE CBT-1 2024-25 17 December 2024 Shift 2 GK Questions – with answers & solutions

All 43 GK / GS questions asked in RRB JE CBT-1 2024-25 on 17 December 2024 Shift 2, with correct answers and short solutions, subject-wise: Biology, Chemistry, Physics, Economics, Polity, Current Affairs.

📚 43 questions🗓️ 17 December 2024⏰ Shift 2
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Subjects: Biology (10) · Chemistry (9) · Physics (9) · Economics (3) · Polity (3) · Current Affairs (4) · Static GK (2) · Geography (1) · Modern History (1) · Medieval History (1)

Biology (10)

Reproduction · Pollination and fertilisation in plants

Q1. What develops into fruit after fertilisation?

  1. (a) Stigma
  2. (b) Anther
  3. (c) Style
  4. (d) Ovary
Answer & solution

Answer: (d) Ovary

Answer: Option 4 — Ovary
After fertilisation the ovary grows and ripens into the fruit.
The ovules inside it become the seeds.
Revision note — Post-fertilisation changes in a flower
• Ovary → fruit; ovule → seed; zygote → embryo; ovary wall → pericarp (fruit wall).
• Petals, sepals, stamens, style and stigma usually wither and fall off.
• The female part is the pistil (carpel) = stigma + style + ovary.
• The male part is the stamen = anther (makes pollen) + filament.
• Pollination is the transfer of pollen from anther to stigma; fertilisation is the fusion of the male and female gametes to form a zygote.
• The pollen tube grows through the style to reach the ovule in the ovary.
Do not mix these up
• Ovary vs ovule — the ovary becomes the fruit; the ovule becomes the seed.
Also asked from this topic: the female reproductive part of a flower (gynoecium / pistil); the meaning of fertilisation (fusion of gametes).
Reproduction · Reproductive health and contraception

Q2. Which of the following diseases can be prevented by using a mechanical barrier contraceptive method?

  1. (a) TB
  2. (b) Typhoid
  3. (c) AIDS
  4. (d) Malaria
Answer & solution

Answer: (c) AIDS

Answer: Option 3 — AIDS
A mechanical barrier (condom) stops the exchange of body fluids, so it prevents sexually transmitted infections such as AIDS (HIV).
TB, typhoid and malaria spread by air, contaminated food/water and mosquitoes — a barrier cannot stop them.
Revision note — Contraceptive methods (Class 10)
• Barrier (mechanical): condom, diaphragm, cervical cap — the only group that also protects against STDs.
• Chemical / hormonal: oral pills change hormonal balance so eggs are not released.
• IUCDs: copper-T and loop placed in the uterus.
• Surgical: vasectomy (vas deferens blocked in males) and tubectomy (fallopian tube blocked in females) — permanent, no STD protection.
• STDs: bacterial — gonorrhoea, syphilis; viral — warts, HIV-AIDS.
• Spread of disease: TB — air (bacterium); typhoid — food and water (bacterium); malaria — female Anopheles mosquito (protozoan Plasmodium).
Also asked from this topic: a limitation of surgical contraception (it does not prevent sexually transmitted infections).
Reproduction · Asexual reproduction (fission, budding, fragmentation, spores)

Q3. Which of the following is true about asexual reproduction?

  1. (a) It requires complex reproductive organs.
  2. (b) It requires fertilisation.
  3. (c) It involves two parent organisms.
  4. (d) It results in offspring genetically identical to the parent.
Answer & solution

Answer: (d) It results in offspring genetically identical to the parent.

Answer: Option 4 — It results in offspring genetically identical to the parent.
Asexual reproduction uses a single parent and no gametes, so the offspring are copies (clones) of the parent.
The other three options describe sexual reproduction.
Revision note — Modes of asexual reproduction
• Fission: binary in Amoeba, Paramecium; multiple in Plasmodium.
• Budding: Hydra, yeast.
• Fragmentation: Spirogyra; regeneration: Planaria, Hydra.
• Spore formation: Rhizopus (bread mould) — spores in sporangia.
• Vegetative propagation: potato (stem), Bryophyllum (leaf), sugarcane, rose (cutting).
• No fertilisation, no meiosis — so little variation; variation arises only from small DNA copying errors.
Do not mix these up
• Asexual vs sexual — one parent, no gametes, identical offspring vs two parents, gametes fuse, variation.
Also asked from this topic: what Amoeba, yeast and Hydra reproducing with one parent shows (no fusion of gametes); a benefit of vegetative propagation (genetically identical plants).
Reproduction · Reproductive health and contraception

Q4. Besides being a barrier method of contraception, condoms also serve which of the following purposes?

  1. (a) Help in transmission of STDs such as gonorrhoea
  2. (b) Prevent diseases that spread through skin-to-skin contact
  3. (c) Decrease sexual desire
  4. (d) Prevent transmission of STDs such as gonorrhoea
Answer & solution

Answer: (d) Prevent transmission of STDs such as gonorrhoea

Answer: Option 4 — Prevent transmission of STDs such as gonorrhoea
A condom forms a physical barrier between partners, so it blocks sexually transmitted diseases such as gonorrhoea, syphilis and HIV-AIDS.
Revision note — Sexually transmitted diseases
• Bacterial STDs: gonorrhoea, syphilis.
• Viral STDs: genital warts, HIV-AIDS.
• Condom — the only contraceptive that gives dual protection: against pregnancy and STDs.
• Copper-T, oral pills and surgery prevent pregnancy but give no protection against STDs.
• HIV attacks the immune system (helper T-cells); spread by unsafe sex, infected blood, shared needles, and from mother to child.
Also asked from this topic: a limitation of surgical contraception (it does not prevent sexually transmitted infections).
Reproduction · Asexual reproduction (fission, budding, fragmentation, spores)

Q5. The special reproductive structures in fungi like Rhizopus, which germinate to form new individuals, are called:

  1. (a) Gemmules
  2. (b) Pollens
  3. (c) Spores
  4. (d) Anthers
Answer & solution

Answer: (c) Spores

Answer: Option 3 — Spores
In Rhizopus (bread mould) the tiny blob-on-a-stick structures are sporangia, which contain spores. Each spore germinates into a new Rhizopus on a moist surface.
Revision note — Spore formation
• Seen in fungi (Rhizopus, Mucor, Penicillium) and in ferns and mosses.
• Spores are covered by a thick protective wall — they survive until they reach a moist surface.
• Warm and moist conditions favour spore germination — that is why bread moulds in the rainy season.
• Yeast reproduces mainly by budding, not spores.
• Spore formation is asexual — one parent, no gametes.
Do not mix these up
• Gemmules vs spores — gemmules are the internal buds of sponges; spores are the reproductive bodies of fungi.
• Pollen and anthers belong to flowering plants — pollen grains form in the anther of the stamen.
Also asked from this topic: the organism that does not reproduce by spore formation (yeast — it buds); conditions that favour fungal spore germination (warm and moist).
Diseases, Immunity and Health · Viral diseases

Q6. Which of the following statements about AIDS is FALSE?

  1. (a) AIDS can be transmitted through mosquito bites.
  2. (b) AIDS affects the immune system of the body.
  3. (c) AIDS can be prevented by practising safe sex.
  4. (d) AIDS is caused by the HIV virus.
Answer & solution

Answer: (a) AIDS can be transmitted through mosquito bites.

Answer: Option 1 — AIDS can be transmitted through mosquito bites.
This is false. HIV does not multiply inside a mosquito and is not injected with its saliva, so mosquitoes cannot spread AIDS.
The other three statements are true.
Revision note — AIDS and HIV
• AIDS = Acquired Immuno Deficiency Syndrome; caused by HIV (Human Immunodeficiency Virus), a retrovirus.
• HIV destroys helper T-lymphocytes (CD4 cells), so the immune system weakens and ordinary infections become dangerous.
• Spread by: unprotected sexual contact, infected blood transfusion, shared needles/syringes, and mother to child (pregnancy, birth, breastfeeding).
• Not spread by: mosquito bites, handshakes, hugging, sharing food or utensils.
• Prevention: safe sex (condoms), screened blood, sterile needles; no vaccine or cure yet — antiretroviral therapy (ART) controls it.
• First cases reported in 1981; HIV identified in 1983; World AIDS Day — 1 December; screening test: ELISA.
Also asked from this topic: the year the first cases of AIDS were identified (1981).
Reproduction · Asexual reproduction (fission, budding, fragmentation, spores)

Q7. Which of the following is a primary reason why all multi-cellular organisms do not reproduce by fragmentation?

  1. (a) Their cells are loosely organised.
  2. (b) They have a random arrangement of cells.
  3. (c) They have specialised cells organised into tissues and organs.
  4. (d) They are unicellular.
Answer & solution

Answer: (c) They have specialised cells organised into tissues and organs.

Answer: Option 3 — They have specialised cells organised into tissues and organs.
A complex multicellular body is not a random collection of cells. Its specialised cells form tissues, and tissues form organs, each at a fixed place.
A broken fragment lacks most of these, so it cannot grow into a whole organism.
Revision note — Asexual reproduction in multicellular organisms
• Fragmentation: a simple multicellular body breaks into pieces and each piece grows into a new individual — Spirogyra.
• Regeneration: a cut part rebuilds the whole body using specialised cells that divide and differentiate — Planaria, Hydra.
• Budding: an outgrowth forms from regenerative cells and detaches — Hydra; in unicellular yeast too.
• Spore formation: sporangia release spores — Rhizopus (bread mould).
• Vegetative propagation in plants — roots, stems or leaves (Bryophyllum leaf buds, potato, sugarcane, rose).
• Complex organisms therefore rely on specialised reproductive cells and systems instead of simple fragmentation.
Also asked from this topic: what single-parent reproduction in Amoeba, yeast and Hydra shows (no fusion of gametes); why multicellular organisms need specialised systems (inner cells lack contact with the outside).
Reproduction · Reproductive health and contraception

Q8. In surgical procedures for contraception in males, sperm transfer gets prevented if which of the following is blocked?

  1. (a) Testes
  2. (b) Ovary
  3. (c) Vas deferens
  4. (d) Fallopian tubes
Answer & solution

Answer: (c) Vas deferens

Answer: Option 3 — Vas deferens
In the male surgical method (vasectomy) the vas deferens is cut and tied, so sperms made in the testes cannot reach the urethra.
Ovary and fallopian tubes belong to the female system.
Revision note — Contraception and the male reproductive system (Class 10)
• Vasectomy — vas deferens blocked (male); tubectomy — fallopian tube (oviduct) blocked (female).
• Barrier methods — condoms; the only methods that also protect against sexually transmitted diseases.
• Hormonal methods — oral pills change the hormonal balance so that eggs are not released.
• Copper-T / loop — placed in the uterus to prevent pregnancy.
• Testes make sperms and testosterone; they lie in the scrotum because sperm formation needs a temperature lower than body temperature.
• Sperms travel through the vas deferens to the urethra; seminal vesicles and the prostate gland add fluid that makes up the semen.
Do not mix these up
• Vasectomy vs tubectomy — "vas" = male (vas deferens); "tube" = female (fallopian tube).
Also asked from this topic: a limitation of surgical contraception (it does not prevent sexually transmitted diseases); the structure that is not part of the male reproductive system (fallopian tube).
Heredity and Evolution · Chromosomes, genes and DNA

Q9. What are the number of chromosomes in a human male germ cell?

  1. (a) 46 Chromosomes
  2. (b) 23 pairs of Chromosomes
  3. (c) 46 pairs of Chromosomes
  4. (d) 23 Chromosomes
Answer & solution

Answer: (d) 23 Chromosomes

Answer: Option 4 — 23 Chromosomes
A germ cell (gamete) is formed by meiosis, which halves the chromosome number.
So a human sperm carries only 23 single chromosomes (not pairs) — 22 autosomes + X or Y.
Revision note — Chromosomes and sex determination in humans
• Human body (somatic) cells are diploid: 46 chromosomes = 23 pairs.
• Of these, 22 pairs are autosomes and 1 pair is the sex chromosomes.
• Female: XX; male: XY.
• Gametes are haploid (n = 23): every egg carries 22 + X; a sperm carries 22 + X or 22 + Y.
• Fertilisation restores the number: sperm (23) + egg (23) = zygote (46).
• The sex of the child is decided by the father's sperm — a Y-sperm gives a boy, an X-sperm gives a girl.
Do not mix these up
• 23 chromosomes vs 23 pairs — a gamete has 23 unpaired chromosomes; 23 pairs (46) is a body cell.
Also asked from this topic: the number of pairs of autosomes in humans (22); the number of chromosomes a human zygote should have (46); the name for haploid reproductive cells like sperm and eggs (gametes).
Heredity and Evolution · Mendel's laws and experiments

Q10. Mendel studied traits such as flower colour and seed shape in pea plants. These traits are called as:

  1. (a) progeny units
  2. (b) visible characters
  3. (c) genetic codes
  4. (d) dominant characteristics
Answer & solution

Answer: (b) visible characters

Answer: Option 2 — visible characters
Mendel chose contrasting visible characters of the garden pea — tall/short plants, round/wrinkled seeds, violet/white flowers — that could be seen and counted in each generation.
NCERT calls these traits visible characters.
Revision note — Mendel's experiments on the garden pea
• Gregor Johann Mendel — the father of genetics; worked on Pisum sativum (garden pea).
• He studied 7 pairs of contrasting characters, e.g. tall/dwarf, round/wrinkled seed, yellow/green seed, violet/white flower.
• Monohybrid cross (tall × dwarf): F1 all tall; F2 tall : dwarf = 3 : 1; genotype ratio 1 : 2 : 1.
• Dihybrid cross: F2 = 9 : 3 : 3 : 1 — shows independent inheritance of traits.
• The trait seen in F1 is dominant (T); the hidden one is recessive (t); TT and Tt are tall, only tt is short.
• Mendel's "factors" are today's genes.
Do not mix these up
• Visible characters vs dominant characteristics — both forms of a character (e.g. violet and white) are visible characters; only one of them is dominant.
Also asked from this topic: the trait tallness shown by all F1 plants of a tall × dwarf cross (dominant trait); the genotype of a short pea plant (tt).

Chemistry (9)

Metals and Non-metals · Reactivity series

Q11. When a metal and sulphuric acid react with each other, metal displaces hydrogen, which is higher in the reactivity series. Identify the metal for which the bubbling of hydrogen gas will be the fastest.

  1. (a) Aluminium
  2. (b) Zinc
  3. (c) Iron
  4. (d) Magnesium
Answer & solution

Answer: (d) Magnesium

Answer: Option 4 — Magnesium
The more reactive the metal, the faster it displaces hydrogen from a dilute acid.
Of the four, magnesium is the highest in the reactivity series, so it bubbles fastest.
Mg + H_(2)SO_(4) → MgSO_(4) + H_(2)↑
Revision note — Reactivity series and acids
• Order to remember: K > Na > Ca > Mg > Al > Zn > Fe > Pb > H > Cu > Hg > Ag > Au.
• For these options: Mg > Al > Zn > Fe — so the speed of bubbling falls in the same order.
• Only metals above hydrogen release H_(2) gas with dilute acids; Cu, Ag, Au do not.
• Metal + dilute acid → salt + hydrogen; hydrogen burns with a pop sound.
• Aluminium starts slowly because of its protective oxide layer (Al_(2)O_(3)).
• Nitric acid usually does not give H_(2) (it is an oxidising agent) — except Mg and Mn with very dilute HNO_(3).
Do not mix these up
• Aluminium vs magnesium — Al is below Mg in the series, and its oxide coat slows it further.
Also asked from this topic: which metals do not give hydrogen with dilute acids (those below hydrogen, like Cu, Ag, Au); the product formed with hydrogen when a metal reacts with an acid (salt).
Chemical Reactions and Equations · Writing and balancing chemical equations

Q12. Which of the following is true for a balanced chemical equation?

  1. (a) The products have more atoms than the reactants.
  2. (b) The mass of reactants is always greater than the mass of products.
  3. (c) The total number of atoms for each element is the same on both sides of the equation.
  4. (d) The number of molecules on each side is always equal.
Answer & solution

Answer: (c) The total number of atoms for each element is the same on both sides of the equation.

Answer: Option 3 — The total number of atoms for each element is the same on both sides of the equation.
Atoms are neither created nor destroyed in a reaction, so each element must have the same number of atoms on both sides.
This follows the law of conservation of mass.
Revision note — Balancing chemical equations
• A balanced equation obeys the law of conservation of mass (Lavoisier).
• Total mass of reactants = total mass of products.
• Balance by changing only the coefficients — never the subscripts in a formula.
• The number of molecules need not match: 2H_(2) + O_(2) → 2H_(2)O has 3 molecules on the left and 2 on the right.
• Method: hit and trial — start with the compound having the most atoms.
• Example: 3Fe + 4H_(2)O → Fe_(3)O_(4) + 4H_(2).
• State symbols: (s), (l), (g), (aq).
Do not mix these up
• Atoms vs molecules — atoms of each element balance; molecules on each side can differ.
Also asked from this topic: the reaction that violates conservation of mass (2Mg + O_(2) → MgO, which is unbalanced); what may not be changed while balancing (the formula of a substance).
Acids, Bases and Salts · Common salts - preparation and uses (baking soda, washing soda, bleaching powder, plaster of Paris)

Q13. What is the molecular formula of washing soda?

  1. (a) NaHCO₃
  2. (b) Na₂CO₃
  3. (c) NaCl
  4. (d) Na₂CO₃·10H₂O
Answer & solution

Answer: (d) Na₂CO₃·10H₂O

Answer: Option 4 — Na_(2)CO_(3)·10H_(2)O
Washing soda is sodium carbonate decahydrate — sodium carbonate with 10 molecules of water of crystallisation.
Revision note — Common sodium and calcium salts
• Washing soda: Na_(2)CO_(3)·10H_(2)O; made by recrystallising soda ash (Na_(2)CO_(3)).
• Baking soda: NaHCO_(3) — sodium hydrogencarbonate; used in antacids and soda-acid fire extinguishers.
• Common salt: NaCl; its brine gives NaOH, Cl_(2) and H_(2) in the chlor-alkali process.
• Bleaching powder: CaOCl_(2); Plaster of Paris: CaSO_(4)·½H_(2)O; Gypsum: CaSO_(4)·2H_(2)O.
• Uses of washing soda: glass, soap and paper industries, making borax, household cleaning, removing permanent hardness of water.
Do not mix these up
• Na_(2)CO_(3) vs Na_(2)CO_(3)·10H_(2)O — the anhydrous form is soda ash; washing soda is the decahydrate.
• Washing soda vs baking soda — carbonate (Na_(2)CO_(3)) vs hydrogencarbonate (NaHCO_(3)).
Also asked from this topic: industries that use washing soda (glass, soap and paper); the gas needed with ammonia to prepare baking soda (carbon dioxide).
Chemical Reactions and Equations · Double displacement and precipitation reactions

Q14. A double displacement reaction typically involves the exchange of:

  1. (a) electrons
  2. (b) protons
  3. (c) neutrons
  4. (d) ions
Answer & solution

Answer: (d) ions

Answer: Option 4 — ions
In a double displacement reaction two compounds exchange ions to form two new compounds: AB + CD → AD + CB.
Revision note — Double displacement reactions
• Example: Na_(2)SO_(4) + BaCl_(2) → BaSO_(4) + 2NaCl — white precipitate of barium sulphate.
• When an insoluble solid forms, it is also called a precipitation reaction.
• Pb(NO_(3))_(2) + 2KI → PbI_(2) + 2KNO_(3) — yellow precipitate of lead iodide.
• Neutralisation (acid + base → salt + water) is also a double displacement reaction.
• Compare: displacement — a more reactive element pushes out a less reactive one (Fe + CuSO_(4) → FeSO_(4) + Cu).
Do not mix these up
• Displacement vs double displacement — one element replaces another vs two compounds swap ions.
Also asked from this topic: the main characteristic of a double displacement reaction (exchange of ions between reactants); the precipitate when barium chloride and sodium sulphate solutions mix (barium sulphate).
Environmental Chemistry · Acid rain

Q15. When the pH of rainwater falls below 5.6, it is commonly referred to as:

  1. (a) acid rain
  2. (b) mineral rain
  3. (c) hard water
  4. (d) alkaline rain
Answer & solution

Answer: (a) acid rain

Answer: Option 1 — acid rain
Normal rain is slightly acidic (pH about 5.6) because of dissolved carbon dioxide. When the pH falls below 5.6, it is called acid rain.
Revision note — Acid rain
• Caused mainly by sulphur dioxide (SO_(2)) and nitrogen oxides (NO_(x)) from burning fossil fuels.
• These form sulphuric acid and nitric acid in the atmosphere, which fall with rain.
• Effects: kills aquatic life when lake water pH drops, damages crops and forests, corrodes buildings.
• The Taj Mahal is yellowing from acid rain and pollution ("marble cancer") — marble is CaCO_(3).
• Lower pH = more acidic; pH 7 is neutral; living organisms survive only in a narrow pH range (7.0 to 7.8) in the body.
Also asked from this topic: the main gas behind acid rain (sulphur dioxide); the two gases mainly responsible (sulphur dioxide and nitrogen oxides).
Chemical Reactions and Equations · Double displacement and precipitation reactions

Q16. Which of the following statements best describes what happens in a double displacement reaction?

  1. (a) A compound breaks down into simpler substances.
  2. (b) Electrons are transferred between atoms.
  3. (c) Ions in two compounds switch places to form two new compounds.
  4. (d) Two elements combine to form a compound.
Answer & solution

Answer: (c) Ions in two compounds switch places to form two new compounds.

Answer: Option 3 — Ions in two compounds switch places to form two new compounds.
In a double displacement reaction two compounds exchange ions: AB + CD → AD + CB.
Example: Na_(2)SO_(4) + BaCl_(2) → BaSO_(4) (white precipitate) + 2NaCl.
Revision note — Types of chemical reactions (Class 10)
• Combination: two or more substances form one product — CaO + H_(2)O → Ca(OH)_(2) (slaked lime).
• Decomposition: one compound breaks into simpler substances — by heat (CaCO_(3)), electricity (water) or light (AgCl).
• Displacement: a more reactive element pushes out a less reactive one — Fe + CuSO_(4) → FeSO_(4) + Cu.
• Double displacement: exchange of ions; when an insoluble solid forms it is a precipitation reaction.
• Redox: gain of oxygen / loss of hydrogen = oxidation; the reverse = reduction; electron transfer is the redox idea.
• Neutralisation (acid + base → salt + water) is also a double displacement reaction.
Do not mix these up
• Displacement vs double displacement — displacement: an element replaces another (one swap); double displacement: two compounds swap partners (two swaps).
Also asked from this topic: why Na_(2)SO_(4) + BaCl_(2) is a double displacement reaction (exchange of ions); two salt solutions giving an insoluble solid (precipitation reaction).
Chemical Reactions and Equations · Double displacement and precipitation reactions

Q17. What is the result when sodium chloride and silver nitrate are mixed in a double displacement reaction?

  1. (a) Formation of a precipitate
  2. (b) Formation of a gas
  3. (c) Formation of water
  4. (d) Formation of a salt
Answer & solution

Answer: (a) Formation of a precipitate

Answer: Option 1 — Formation of a precipitate
NaCl(aq) + AgNO_(3)(aq) → AgCl(s) + NaNO_(3)(aq)
The ions swap partners and silver chloride, which is insoluble, separates as a white curdy precipitate.
Revision note — Precipitation reactions
• A precipitate is an insoluble solid formed when two solutions are mixed; the reaction is a double displacement (precipitation) reaction.
• AgNO_(3) + NaCl → AgCl↓ (white) + NaNO_(3) — the standard test for chloride ions.
• Na_(2)SO_(4) + BaCl_(2) → BaSO_(4)↓ (white) + 2NaCl.
• Pb(NO_(3))_(2) + 2KI → PbI_(2)↓ (yellow) + 2KNO_(3).
• AgCl turns grey in sunlight: 2AgCl → 2Ag + Cl_(2) — a photolytic decomposition, used in black-and-white photography.
Do not mix these up
• Precipitate vs salt — AgCl and NaNO_(3) are both salts, but the observable result that marks this reaction is the insoluble precipitate.
Also asked from this topic: the name of the white insoluble solid formed in a double displacement reaction (precipitate); which compound shows a visible change in sunlight (silver chloride).
Acids, Bases and Salts · Common salts - preparation and uses (baking soda, washing soda, bleaching powder, plaster of Paris)

Q18. What is the difference between baking powder and baking soda?

  1. (a) Baking powder is a mixture of baking soda and hydrochloric acid.
  2. (b) Baking soda is a mixture of baking powder and hydrochloric acid.
  3. (c) Baking soda is a mixture of baking powder and tartaric acid.
  4. (d) Baking powder is a mixture of baking soda and tartaric acid.
Answer & solution

Answer: (d) Baking powder is a mixture of baking soda and tartaric acid.

Answer: Option 4 — Baking powder is a mixture of baking soda and tartaric acid.
Baking soda is a single compound, sodium hydrogencarbonate (NaHCO_(3)).
Baking powder = baking soda + a mild edible acid such as tartaric acid.
Revision note — Baking soda and baking powder (Class 10)
• Baking soda is made from NaCl + H_(2)O + CO_(2) + NH_(3) → NH_(4)Cl + NaHCO_(3).
• On heating: 2NaHCO_(3) → Na_(2)CO_(3) + H_(2)O + CO_(2); the Na_(2)CO_(3) left behind makes cake bitter.
• In baking powder the tartaric acid neutralises this, so the cake is not bitter.
• With water or heat, baking powder gives off CO_(2), which makes bread and cake soft and spongy.
• Other uses of baking soda: antacid (neutralises excess stomach acid) and soda-acid fire extinguishers.
• Washing soda is Na_(2)CO_(3)·10H_(2)O — a different salt.
Do not mix these up
• Baking soda vs washing soda — NaHCO_(3) (cooking, antacid) vs Na_(2)CO_(3)·10H_(2)O (cleaning, removing permanent hardness).
Also asked from this topic: chemical name of baking soda (sodium hydrogencarbonate); why it is used in fire extinguishers (it readily releases CO_(2)); gas needed with ammonia to make it (carbon dioxide).
Acids, Bases and Salts · pH scale and its importance

Q19. What is the pH of a solution containing significant concentrations of H⁺ ions?

  1. (a) Less than 7
  2. (b) Cannot be determined
  3. (c) Greater than 7
  4. (d) 7
Answer & solution

Answer: (a) Less than 7

Answer: Option 1 — Less than 7
A high concentration of H⁺ ions makes a solution acidic, and acidic solutions have a pH below 7.
The more H⁺ ions, the lower the pH.
Revision note — The pH scale (Class 10)
• pH = "potenz" (power) of hydrogen; pH = −log[H⁺]; the scale runs from 0 to 14.
• pH < 7 → acidic; pH = 7 → neutral (pure water); pH > 7 → basic.
• Each unit change means a 10-fold change in H⁺ concentration.
• Universal indicator shows different colours at different pH values.
• Stomach juice (HCl) ≈ pH 2; blood ≈ 7.4; tooth decay starts when the mouth's pH falls below 5.5; acid rain has pH below 5.6.
• Plants and animals survive only in a narrow pH range (about 7.0 to 7.8 in our body).
Do not mix these up
• H⁺ vs OH⁻ — more H⁺ ions: acidic, pH down; more OH⁻ ions: basic, pH up.
Also asked from this topic: what a higher H⁺ concentration corresponds to (a lower pH); the neutral substance on the pH scale (pure water, pH 7); lowest H⁺ among seawater, blood, milk, vinegar (seawater).

Physics (9)

Light - Refraction and Lenses · Refractive index and optical density

Q20. Which of the following statements is true regarding the refractive index?

  1. (a) Refractive index of glass is less than 1.
  2. (b) Refractive index of a given medium is independent of the wavelength of the light.
  3. (c) Refractive index depends only on the speed of light in vacuum.
  4. (d) Refractive index of water is always greater than 1.
Answer & solution

Answer: (d) Refractive index of water is always greater than 1.

Answer: Option 4 — Refractive index of water is always greater than 1.
Refractive index n = speed of light in vacuum ÷ speed of light in the medium.
Light is slower in water than in vacuum, so n of water (1.33) is more than 1.
Revision note — Refractive index
• n = c ÷ v; it is a ratio of two speeds, so it has no unit.
• Values: vacuum 1, air 1.0003, water 1.33, crown glass 1.52, diamond 2.42 (highest among common media).
• Every material medium has n > 1, because light is fastest in vacuum.
• n depends on the wavelength — violet light has a larger n than red, which is why a prism causes dispersion.
• Higher n = optically denser medium; light going into it bends towards the normal.
• Relative index n₂₁ = v₁ ÷ v₂ (speed in medium 1 ÷ speed in medium 2).
Do not mix these up
• Optical density vs mass density — kerosene is optically denser than water but lighter than water.
Also asked from this topic: the refractive index of a solid where light slows from 3 × 10⁸ m/s to 2 × 10⁸ m/s (1.5); what a refractive index of 1.33 for water means (light travels 1.33 times slower in water than in air).
Magnetism and Magnetic Effects of Current · Magnets and magnetic properties

Q21. Which of the following statements is correct regarding magnets?

  1. (a) A magnet can attract an electron.
  2. (b) A magnet produces magnetic as well as electric fields.
  3. (c) A magnet is a dipole with north and south poles.
  4. (d) A magnet can have either north or south pole.
Answer & solution

Answer: (c) A magnet is a dipole with north and south poles.

Answer: Option 3 — A magnet is a dipole with north and south poles.
Every magnet has two poles — north and south — so it is a magnetic dipole.
Breaking a magnet only gives smaller magnets, each with both poles.
Revision note — Magnets and magnetic poles
• Isolated magnetic poles (monopoles) do not exist; poles always come in N–S pairs.
• A freely suspended magnet rests in the north–south direction.
• Like poles repel, unlike poles attract; repulsion is the sure test of a magnet.
• Magnetic field lines go from N to S outside and S to N inside, forming closed loops.
• Field lines never cross each other; they are crowded where the field is strong (near the poles).
• A stationary magnet produces only a magnetic field, no electric field.
Do not mix these up
• Magnetic vs electric force — a magnet attracts iron, nickel, cobalt; it does not attract a stationary electron (charge).
Also asked from this topic: the property of field lines showing there are no monopoles (they form closed loops); the pattern of field lines of a solenoid (like a bar magnet).
Light - Reflection and Mirrors · Spherical mirror terminology

Q22. For a concave mirror, where is the centre of curvature located relative to the mirror?

  1. (a) Behind the mirror
  2. (b) At the mirror's focal point
  3. (c) In front of the mirror
  4. (d) At the mirror’s surface
Answer & solution

Answer: (c) In front of the mirror

Answer: Option 3 — In front of the mirror
A concave mirror's reflecting surface curves inward, so the centre of the sphere it is cut from lies on the reflecting side — in front of the mirror.
C lies at a distance R = 2f from the pole, beyond the focus.
Revision note — Spherical mirror terms
• Pole (P): centre of the mirror's surface; principal axis: line through P and C.
• Centre of curvature (C): centre of the sphere of which the mirror is a part — in front for a concave mirror, behind for a convex mirror.
• Radius of curvature (R): distance PC; focal length f = R/2.
• Principal focus (F): lies midway between P and C; real for concave, virtual for convex.
• A ray through C strikes the mirror along the normal and retraces its path.
• Sign convention: for a concave mirror f and R are negative (measured against the incident light).
Do not mix these up
• Concave vs convex — C and F are in front of a concave mirror, behind a convex mirror.
Also asked from this topic: the path of a ray passing through the centre of curvature (it retraces its path); where the focus of a convex mirror of R = 50 cm lies (25 cm behind the mirror).
Physics Miscellaneous · Physics in daily life

Q23. Which electrical appliance helps preserve food by maintaining low temperatures?

  1. (a) Toaster
  2. (b) Microwave
  3. (c) Refrigerator
  4. (d) Electric kettle
Answer & solution

Answer: (c) Refrigerator

Answer: Option 3 — Refrigerator
A refrigerator keeps food at a low temperature, which slows the growth of bacteria and fungi, so food stays fresh longer.
A toaster, microwave and electric kettle all heat food or water.
Revision note — How a refrigerator cools
• It pumps heat out of the food compartment and releases it at the back (the black condenser coils) — so the back feels warm.
• The refrigerant absorbs heat as it evaporates inside the cooling pipes — evaporation causes cooling.
• A compressor squeezes the vapour back into liquid so the cycle repeats.
• Older refrigerators used CFCs, which deplete the ozone layer; they are being phased out under the Montreal Protocol (1987).
• Low temperature slows microbial growth and enzyme action — the basis of food preservation by cold storage.
• Appliances like toaster, electric kettle, iron and heater work on the heating effect of current.
Also asked from this topic: a device that earlier used CFCs extensively (refrigerator).
Light - Reflection and Mirrors · Concave mirror - image formation and uses

Q24. If the object is placed beyond the center of curvature (C) in front of a concave mirror, the image formed will be ___________.

  1. (a) virtual, upright and diminished
  2. (b) real, inverted and enlarged
  3. (c) real, inverted and diminished
  4. (d) virtual, upright and enlarged
Answer & solution

Answer: (c) real, inverted and diminished

Answer: Option 3 — real, inverted and diminished
With the object beyond C, a concave mirror forms the image between F and C — real, inverted and diminished.
Revision note — Image formation by a concave mirror
• Object at infinity → image at F; real, inverted, highly diminished (point-sized).
• Object beyond C → image between F and C; real, inverted, diminished.
• Object at C → image at C; real, inverted, same size.
• Object between C and F → image beyond C; real, inverted, enlarged.
• Object at F → image at infinity; real, inverted, highly enlarged.
• Object between P and F → image behind the mirror; virtual, erect, enlarged (shaving / make-up mirror).
• R = 2f; a concave mirror is converging — used in torches, headlights, solar furnaces, dentists' mirrors.
Do not mix these up
• Beyond C vs between C and F — diminished vs enlarged; the image and object "swap" regions.
Also asked from this topic: the image when the object is between C and F (real, inverted and enlarged, beyond C); the change as the object moves from beyond C towards F (image grows and moves away).
Magnetism and Magnetic Effects of Current · Magnetic field and field lines

Q25. The magnetic field lines of a bar magnet may NOT be drawn using:

  1. (a) iron filings
  2. (b) wood particles
  3. (c) another bar magnet
  4. (d) a magnetic compass
Answer & solution

Answer: (b) wood particles

Answer: Option 2 — wood particles
Wood is non-magnetic, so its particles do not line up along the field and cannot trace the field lines.
Iron filings, a magnetic compass and another magnet all respond to the field, so each can show the pattern.
Revision note — Magnetic field lines (Class 10)
• Outside a magnet the field lines run from the north pole to the south pole; inside, from south to north — they are closed curves.
• Two field lines never cross — at a crossing the compass would point in two directions at once.
• Where lines are closer together, the field is stronger (crowded near the poles).
• The tangent to a field line at a point gives the direction of the field there.
• A compass needle is a small bar magnet; its north end points along the field line.
• Iron filings sprinkled round a magnet and gently tapped arrange themselves along the field lines.
Do not mix these up
• Magnetic vs non-magnetic — iron, nickel, cobalt respond to a magnet; wood, plastic, paper, copper do not.
Also asked from this topic: what closely spaced field lines show (a stronger magnetic field); the pattern of field lines inside a current-carrying solenoid (parallel straight lines).
A compass needle is itself a tiny bar magnet — that is why it can plot the field line by line.
Electricity · Ohm's law

Q26. If the resistance in a circuit is increased while the voltage remains constant, the current will __________.

  1. (a) remain constant
  2. (b) increase
  3. (c) double
  4. (d) decrease
Answer & solution

Answer: (d) decrease

Answer: Option 4 — decrease
By Ohm's law, I = V ÷ R.
With V fixed, current is inversely proportional to resistance — more resistance means less current.
Revision note — Ohm's law
• Statement: at constant temperature, the current through a conductor is directly proportional to the potential difference across it: V = IR.
• R = V ÷ I; SI unit ohm (Ω) = 1 volt per ampere.
• At constant V: doubling R halves I; halving R doubles I.
• The V–I graph of an ohmic conductor is a straight line through the origin; its slope gives R.
• Resistance itself depends on length, area of cross-section, material and temperature, not on V or I.
Do not mix these up
• Current vs resistance — changing V changes I, but the resistance of the conductor stays the same.
Also asked from this topic: what happens to the current when the resistance is doubled at constant voltage (it halves); the quantity measured in volt per ampere (resistance, unit ohm).
Light - Refraction and Lenses · Numericals on refraction and lenses

Q27. If the refractive index of water is 1.33, then the speed of light in water is approximately ___________.

  1. (a) 1.5×10⁸ m/s
  2. (b) 2.26×10⁸ m/s
  3. (c) 4×10⁸ m/s
  4. (d) 3×10⁸ m/s
Answer & solution

Answer: (b) 2.26×10⁸ m/s

Formula — refractive index.
Refractive index = speed of light in vacuum ÷ speed of light in the medium
n = c ÷ v ⇒ v = c ÷ n
Substitute.
c = 3 × 10^(8) m/s, n = 1.33
v = 3 × 10^(8) ÷ 1.33
= 2.26 × 10^(8) m/s
Answer: 2.26 × 10^(8) m/s
Revision note — Refractive index and speed of light
• Light is fastest in vacuum (3 × 10^(8) m/s); every medium has n > 1.
• Speeds: water (n = 1.33) about 2.25 × 10^(8) m/s; glass (n = 1.5) 2 × 10^(8) m/s; diamond (n = 2.42) about 1.24 × 10^(8) m/s.
• Higher n ⇒ optically denser ⇒ slower light.
• On refraction the speed and wavelength change, but the frequency stays the same.
Any answer above 3 × 10^(8) m/s is impossible — light can never travel faster in water than in vacuum.
Also asked from this topic: the speed of light in glass of refractive index 1.5 (2 × 10^(8) m/s); the property of light that does not change on refraction (frequency).
Electricity · Numericals on electricity

Q28. The number of 176-Ω resistors (in parallel) required to carry 5 A on a 220-V line is:

  1. (a) 4
  2. (b) 8
  3. (c) 2
  4. (d) 16
Answer & solution

Answer: (a) 4

Formula — current through each resistor.
In parallel every resistor gets the full 220 V.
Current in one resistor = V ÷ R (Ohm's law)
= 220 ÷ 176 = 1.25 A
Number of resistors.
Total current = number × current in each
n = 5 ÷ 1.25 = 4
Short trick.
Required total resistance = 220 ÷ 5 = 44 Ω
n equal resistors R in parallel give R ÷ n.
176 ÷ n = 44 ⇒ n = 4
Answer: 4 resistors
Revision note — Resistors in parallel
• 1/R_(p) = 1/R_(1) + 1/R_(2) + …; n equal resistors R give R ÷ n.
• The voltage is the same across each branch; the currents add up.
• R_(p) is less than the smallest single resistance.
• Household appliances are joined in parallel so each gets the full voltage and can be switched separately.
Multiplying 176 by 4 treats them as a series combination — in parallel the resistance falls, it does not rise.
Also asked from this topic: the total current when 4 Ω and 12 Ω in parallel are joined to a 6 V supply (2 A); how the equivalent resistance of a parallel combination compares with the resistors (less than the smallest).

Economics (3)

Industry and Infrastructure · Public sector undertakings (Maharatna, Navratna, Miniratna)

Q29. Which status was conferred upon Shipping Corporation of India (SCI) by the Government of India in August 2008?

  1. (a) Miniratna
  2. (b) Maharatna
  3. (c) Dashratna
  4. (d) Navratna
Answer & solution

Answer: (d) Navratna

Answer: Option 4 — Navratna
The Government of India granted Navratna status to the Shipping Corporation of India (SCI) in August 2008.
Revision note — CPSE status categories
• Maharatna (introduced 2009–10) — highest status; a board can invest up to ₹5,000 crore in a project without government approval.
• Navratna (introduced 1997) — investment up to ₹1,000 crore or 15% of net worth in one project.
• Miniratna (Category I and II) — for smaller consistently profit-making CPSEs.
• SCI was set up in 1961 (merger of Eastern Shipping and Western Shipping Corporations); HQ Mumbai; under the Ministry of Ports, Shipping and Waterways.
• Maharatna examples: ONGC, NTPC, IOCL, SAIL, BHEL, Coal India, GAIL.
• Navratna examples: BEL, HAL, RCF, Container Corporation (CONCOR).
• "Dashratna" is not a CPSE category.
Also asked from this topic: what Navratna status gives a CPSE (greater managerial and financial autonomy); the CPSE status of Bharat Electronics Limited (Navratna).
Money and Banking · Monetary policy tools (repo, reverse repo, CRR, SLR, MSF, bank rate)

Q30. What is the primary reason for a central bank to increase the reserve requirement ratio of commercial banks?

  1. (a) To decrease the money supply in the economy
  2. (b) To increase the money supply in the economy
  3. (c) To decrease the profitability of commercial banks
  4. (d) To encourage banks to lend more
Answer & solution

Answer: (a) To decrease the money supply in the economy

Answer: Option 1 — To decrease the money supply in the economy
A higher reserve requirement makes banks keep a larger share of deposits as reserves, so less is left to lend.
Less lending means less credit creation — the money supply falls. It is a contractionary step, used mainly to control inflation.
Revision note — RBI's quantitative tools of monetary policy
• CRR (Cash Reserve Ratio): share of deposits kept as cash with the RBI; earns no interest. Dec 2024: RBI cut CRR from 4.5% to 4%.
• SLR (Statutory Liquidity Ratio): share of deposits kept by the bank itself in cash, gold or approved government securities (18%).
• Repo rate: rate at which RBI lends to banks short-term (6.5% in Dec 2024); the main policy rate.
• Reverse repo / SDF: rate at which RBI absorbs surplus funds from banks.
• Open market operations: RBI buying securities injects money; selling withdraws it.
• Raise CRR, SLR or repo ⇒ tight money; cut them ⇒ easy money. Simple money multiplier = 1 ÷ reserve ratio.
• As of 2026: the CRR stands at 3% after the 2025 cuts.
Do not mix these up
• CRR vs SLR — CRR is cash parked with the RBI; SLR is liquid assets the bank keeps with itself.
Also asked from this topic: the effect of higher CRR and SLR on bank lending (reduces lending capacity); a qualitative, not quantitative, RBI tool (moral suasion); the RBI's main policy instrument (repo rate).
Public Finance - Budget and Taxation · Union Budget - latest highlights

Q31. Which of the following statements is INCORRECT about the Annual Financial Statement 2024-25?1) The Budget 2024-25 will focus on four castes.2) 1 crore farmers across the country will be initiated into natural farming, supported by certification and branding in the next 2 years.3) 20,000 need-based bio-input resource centres to be established.4) 1,000 Industrial Training Institutes will be upgraded in hub and spoke arrangements with outcome orientation.

  1. (a) 4 only
  2. (b) 2 only
  3. (c) 3 only
  4. (d) 1 only
Answer & solution

Answer: (c) 3 only

Answer: Option 3 — 3 only
The Budget 2024-25 announced 10,000 need-based bio-input resource centres, not 20,000, so statement 3 is incorrect.
The other three are taken from the budget speech of 23 July 2024.
Revision note — Union Budget 2024-25 (23 July 2024)
• Presented by Nirmala Sitharaman — her 7th consecutive budget; the Annual Financial Statement is the budget under Article 112.
• The focus on four "castes" (groups): Garib (poor), Mahilayen (women), Yuva (youth), Annadata (farmers) — first stated in the interim budget of February 2024.
• Nine priorities; Priority 1 = productivity and resilience in agriculture.
• Natural farming: 1 crore farmers to be initiated in the next 2 years, with certification and branding; 10,000 bio-input resource centres.
• Skilling: 1,000 ITIs to be upgraded in a hub-and-spoke arrangement; PM's package of 5 schemes for 4.1 crore youth over 5 years.
• Fiscal deficit target for 2024-25: 4.9% of GDP.
Also asked from this topic: the number of farmers the National Mission on Natural Farming aims to reach (1 crore); the capital expenditure for Indian Railways in 2024-25 (₹2.62 lakh crore).

Polity (3)

Fundamental Rights · Right to Freedom (Articles 19-22)

Q32. Which of the following rights is NOT part of the Right to Life under Article 21 of the Indian Constitution?

  1. (a) Right to Free Legal Aid
  2. (b) Right to Privacy
  3. (c) Right to Livelihood
  4. (d) Right to Property
Answer & solution

Answer: (d) Right to Property

Answer: Option 4 — Right to Property
The Right to Property is not part of Article 21. The 44th Amendment (1978) removed it from the Fundamental Rights; it is now a constitutional legal right under Article 300A.
Free legal aid, privacy and livelihood have all been read into Article 21 by the Supreme Court.
Revision note — Article 21 (Protection of life and personal liberty)
• Text: no person shall be deprived of life or personal liberty except according to procedure established by law (idea borrowed from Japan).
• Available to all persons — citizens and foreigners.
• Maneka Gandhi case (1978) widened it: the procedure must be fair, just and reasonable.
• Rights read into Article 21: privacy (K.S. Puttaswamy, 2017), livelihood (Olga Tellis, 1985), free legal aid (Hussainara Khatoon, 1979).
• Others read in: clean environment, speedy trial, shelter, health, dignity.
• Article 21A — free and compulsory education for 6–14 years, added by the 86th Amendment (2002).
• Articles 20 and 21 cannot be suspended even during a National Emergency (44th Amendment).
Also asked from this topic: the case that made privacy a Fundamental Right (K.S. Puttaswamy, 2017); the amendment that removed the Right to Property (44th, 1978); source of "procedure established by law" (Japan).
State Government · Special arrangements (Delhi, Puducherry, J&K)

Q33. Which of the following Articles of the Indian Constitution states that there shall be a Legislative Assembly for the National Capital Territory and the seats in such Assembly shall be filled by members chosen by direct election from territorial constituencies in the National Capital Territory?

  1. (a) Article 239 AA
  2. (b) Article 239 B
  3. (c) Article 239A
  4. (d) Article 239 AB
Answer & solution

Answer: (a) Article 239 AA

Answer: Option 1 — Article 239 AA
Article 239AA makes special provisions for Delhi: it names it the National Capital Territory of Delhi and provides a Legislative Assembly elected directly from territorial constituencies.
It was inserted by the 69th Constitutional Amendment Act, 1991.
Revision note — Union Territories in Part VIII (Articles 239–241)
• Article 239 — UTs are administered by the President through an Administrator.
• Article 239A — Parliament may create local legislatures / Council of Ministers for certain UTs (used for Puducherry; added by the 14th Amendment, 1962).
• Article 239AA — Delhi: Legislative Assembly (70 seats), Council of Ministers headed by a Chief Minister, and a Lieutenant Governor.
• Article 239AB — the President may suspend 239AA if the constitutional machinery in Delhi fails.
• Article 239B — the Administrator's power to issue ordinances when the UT legislature is not in session.
• Delhi's Assembly cannot make laws on public order, police and land — these stay with the Centre.
• The Government of NCT of Delhi Act, 1991 put the 69th Amendment into effect.
Do not mix these up
• 239A vs 239AA — 239A is the general enabling article (Puducherry); 239AA is Delhi alone.
Also asked from this topic: the amendment that re-designated Delhi as the National Capital Territory (69th Amendment, 1991); the Act that gave Delhi a legislative assembly (Government of NCT of Delhi Act, 1991).
Parliament · Rajya Sabha

Q34. How many members of the Rajya Sabha are nominated by the President of India?

  1. (a) 12
  2. (b) 15
  3. (c) 10
  4. (d) 8
Answer & solution

Answer: (a) 12

Answer: Option 1 — 12
Under Article 80, the President nominates 12 members to the Rajya Sabha.
They are persons with special knowledge or practical experience in literature, science, art and social service.
Revision note — Rajya Sabha (Council of States)
• Maximum strength 250 = 238 representatives of States and UTs + 12 nominated.
• State members are elected by the elected MLAs by proportional representation through the single transferable vote.
• Seats are allotted to States by the Fourth Schedule; Uttar Pradesh has the most (31).
• It is a permanent House — not dissolved; one-third of members retire every 2 years.
• Term of a member 6 years; minimum age 30 years.
• The Vice-President is the ex-officio Chairman.
• Lok Sabha: President could nominate 2 Anglo-Indians — this ended with the 104th Amendment (2019).
Do not mix these up
• 12 vs 2 — 12 nominated members in Rajya Sabha; the old Anglo-Indian nomination to Lok Sabha was 2.
Also asked from this topic: the Article that lays down the composition of the Rajya Sabha (Article 80); the maximum strength of the Rajya Sabha (250).

Current Affairs (4)

International Affairs and Summits · Summits and conferences

Q35. With respect to Quad Leaders' Summit, which of the following statements is/are correct?1) The Quad Leaders’ Summit was held in Wilmington (US) in 2024.2) The year 2024 marks 22 years since the formation of the grouping.3) India will host the 2025 Quad Leaders Summit.

  1. (a) 1 only
  2. (b) 1 and 2 only
  3. (c) 1 and 3 only
  4. (d) 2 and 3 only
Answer & solution

Answer: (c) 1 and 3 only

Answer: Option 3 — 1 and 3 only
The 2024 Quad Leaders' Summit was hosted by US President Joe Biden at Wilmington, Delaware in September 2024, and the Wilmington Declaration named India as host of the 2025 summit.
Statement 2 is wrong: 2024 marked 20 years, not 22, counted from the 2004 Indian Ocean tsunami response in which the four countries first worked together.
Revision note — Quad (Quadrilateral Security Dialogue)
• Members: India, USA, Japan and Australia; focus: a free, open and inclusive Indo-Pacific.
• Roots: the Tsunami Core Group of 2004; the dialogue was first proposed in 2007 by Japanese PM Shinzo Abe, lapsed, and was revived in 2017.
• First leaders' summit: virtual, March 2021; first in-person summit: Washington D.C., September 2021.
• Later summits: Tokyo (2022), Hiroshima (2023), Wilmington (21 September 2024).
• Wilmington outcomes: the Quad Cancer Moonshot (cervical cancer) and a planned Quad-at-Sea Ship Observer Mission.
Do not mix these up
• 2004 vs 2007 — 2004 is the tsunami cooperation the "20 years" is counted from; 2007 is when the Quad dialogue was first proposed.
Also asked from this topic: the host of the first in-person Quad Leaders' Summit (United States, 2021); when the Quad was first proposed (2007); the primary focus region of the Quad (Indo-Pacific).
Science, Technology and Space - Current · Technology launches and AI

Q36. Students and professors of which IIT have developed an innovative fire rescue drone in June 2024?

  1. (a) IIT Dharwad
  2. (b) IIT Delhi
  3. (c) IIT Mandi
  4. (d) IIT Madras
Answer & solution

Answer: (a) IIT Dharwad

Answer: Option 1 — IIT Dharwad
A team of students and professors of IIT Dharwad (Karnataka) unveiled an innovative fire rescue drone at a workshop on 31 May – 1 June 2024.
Revision note — IIT Dharwad fire rescue drone (June 2024)
• Led by Prof. Sudheer Siddapureddy and Prof. Ameer Mulla of IIT Dharwad.
• Backed by the TiHAN Foundation (the autonomous-navigation technology hub at IIT Hyderabad) with Government of India funding.
• Uses thermal imaging to detect hotspots, track fire spread and judge flame intensity.
• Built with soot-resistant sensors, flexible heat shields and a compact body to move through confined, smoke-filled spaces.
• Also meant for crowd safety at railway stations, malls and pilgrimage centres, and for fire detection at night or in low visibility.
The drone helps firefighters see and locate the fire; it is a detection-and-assessment aid.
Sports - Current · Olympics, Asian Games and Commonwealth Games - current

Q37. Kapil Parmar created history by securing India's first-ever medal in which game at the Paralympic Games 2024?

  1. (a) Shooting
  2. (b) Table Tennis
  3. (c) Fencing
  4. (d) Judo
Answer & solution

Answer: (d) Judo

Answer: Option 4 — Judo
Kapil Parmar won bronze in the men's 60 kg J1 (visually impaired) judo event at the Paris 2024 Paralympics — India's first-ever Paralympic medal in judo.
Revision note — India at the Paris 2024 Paralympics
• Games held 28 August – 8 September 2024 in Paris; India won its best-ever haul of 29 medals (7 gold, 9 silver, 13 bronze).
• Kapil Parmar — first Paralympic judo medal (bronze, 60 kg J1).
• Harvinder Singh — India's first Paralympic archery gold (men's individual recurve open).
• Avani Lekhara — retained her 10 m air rifle SH1 gold; Sumit Antil — javelin F64 gold.
• Navdeep Singh — javelin F41 gold; Praveen Kumar — high jump T64 gold.
• Sheetal Devi and Rakesh Kumar — bronze in the mixed team compound archery event.
Also asked from this topic: India's first Paralympic archery gold at Paris 2024 (Harvinder Singh); the sport of Sheetal Devi's Paris 2024 medal (archery); the javelin F41 gold medallist (Navdeep Singh).
National Affairs and Government Initiatives · New government schemes and missions

Q38. Which of the following Ministries launched the electric mobility promotion scheme in March 2024 to provide short term support to Electric Vehicles?

  1. (a) Ministry of Road Transport and Highways
  2. (b) Ministry of Heavy Industries
  3. (c) Ministry of Environment, Forest and Climate Change
  4. (d) Ministry of Corporate Affairs
Answer & solution

Answer: (b) Ministry of Heavy Industries

Answer: Option 2 — Ministry of Heavy Industries
The Electric Mobility Promotion Scheme (EMPS) 2024 was announced in March 2024 by the Ministry of Heavy Industries (MHI).
It was a short-term scheme to keep EV demand going after FAME-II ended on 31 March 2024.
Revision note — Electric vehicle schemes of India
• EMPS 2024: outlay ₹500 crore, for April–July 2024; later extended to September 2024.
• It gave subsidy for electric two-wheelers (e-2W) and electric three-wheelers (e-3W).
• FAME India (Faster Adoption and Manufacturing of Hybrid and Electric Vehicles): Phase I from 2015, Phase II from 2019 — also under MHI.
• PM E-DRIVE (September 2024, outlay ₹10,900 crore) took over from EMPS for e-2W, e-3W, e-buses, e-ambulances, e-trucks and charging stations.
• PLI for Advanced Chemistry Cell (ACC) battery storage and PLI for Automobile and Auto Components are also run by MHI.
Do not mix these up
• Heavy Industries vs Road Transport — MoRTH handles roads, vehicle registration and rules; EV subsidy schemes sit with MHI.
Also asked from this topic: the 2024 EV scheme with a ₹10,900 crore outlay that subsidises e-2W, e-3W, e-buses and charging infrastructure (PM E-DRIVE).

Static GK (2)

Books and Authors · Modern Indian books and authors

Q39. In which language was the classic Indian novel 'Chandrakanta' originally written?

  1. (a) Hindi
  2. (b) Tamil
  3. (c) Bengali
  4. (d) Urdu
Answer & solution

Answer: (a) Hindi

Answer: Option 1 — Hindi
Chandrakanta (1888) was written in Hindi by Devaki Nandan Khatri.
Its fantasy adventure of tilism (magical mazes) and aiyaars (disguised spies) was so popular that many people are said to have learnt Hindi just to read it.
Revision note — Landmark Hindi novels
• Chandrakanta and its sequel Chandrakanta Santati — Devaki Nandan Khatri; later a TV serial (1994).
• Pariksha Guru (1882) by Lala Srinivas Das — often called the first Hindi novel.
• Godan (1936) — Munshi Premchand; the peasant Hori and his dream of a cow.
• Maila Aanchal (1954) — Phanishwar Nath Renu; the landmark anchalik (regional) novel.
• Tamas (1974) — Bhisham Sahni; communal violence of Partition.
• Ret Samadhi (Tomb of Sand) — Geetanjali Shree; first Hindi novel to win the International Booker Prize (2022), translated by Daisy Rockwell.
Do not mix these up
• Chandrakanta vs Pariksha Guru — Chandrakanta is the famous early popular Hindi novel; Pariksha Guru is usually named the first Hindi novel.
Also asked from this topic: author of Godan (Premchand); of Maila Aanchal (Phanishwar Nath Renu); of Tamas (Bhisham Sahni); first Hindi International Booker winner (Geetanjali Shree).
Monuments and Heritage · Temples and religious places

Q40. What is one of the main attractions of ‘Mamallapuram’ apart from the dance festival?

  1. (a) Modern art galleries
  2. (b) Local handicrafts
  3. (c) Architectural beauty of temples
  4. (d) Wildlife sanctuaries
Answer & solution

Answer: (c) Architectural beauty of temples

Answer: Option 3 — Architectural beauty of temples
Mamallapuram (Mahabalipuram) in Tamil Nadu is famous for its 7th–8th century Pallava rock-cut and structural temples.
The Mamallapuram Dance Festival is itself staged against the backdrop of these monuments.
Revision note — Group of Monuments at Mamallapuram
• Built by the Pallavas; the town is named after Narasimhavarman I "Mamalla".
• Pancha Rathas — five monolithic rock-cut shrines (7th century).
• Shore Temple — structural temple built by Narasimhavarman II (Rajasimha), early 8th century.
• Descent of the Ganges / Arjuna's Penance — a huge open-air bas-relief.
• Carved mainly from granite; an early example of the Dravida style.
• A UNESCO World Heritage Site since 1984.
• The Mamallapuram Dance Festival is held every December–January by Tamil Nadu Tourism.
Also asked from this topic: the ruler who built the Shore Temple (Narasimhavarman II); the rock of which the Mahabalipuram monuments are cut (granite).

Geography (1)

Environment and Protected Areas · Biosphere reserves

Q41. Correctly match the following Biosphere Reserves to their respective states. Biosphere Reserves States1. Nokrek a. Meghalaya2. Panna b. Madhya Pradesh3. Manas c. Assam

  1. (a) 1-b, 2-a, 3-c
  2. (b) 1-a, 2-c, 3-b
  3. (c) 1-c, 2-b, 3-a
  4. (d) 1-a, 2-b, 3-c
Answer & solution

Answer: (d) 1-a, 2-b, 3-c

Answer: Option 4 — 1-a, 2-b, 3-c
Nokrek is in the Garo Hills of Meghalaya, Panna is in Madhya Pradesh and Manas is in Assam.
Revision note — Biosphere reserves of India
• Set up under UNESCO's Man and the Biosphere (MAB) Programme (launched 1971); India has 18 biosphere reserves.
• First: Nilgiri (1986) — Tamil Nadu, Kerala, Karnataka; the first Indian reserve on UNESCO's world network (2000).
• Largest: Great Rann of Kutch (Gujarat); other big ones: Gulf of Mannar, Sundarbans.
• Nokrek (Meghalaya) — Garo Hills; known for wild citrus (Citrus indica); UNESCO network 2009.
• Panna (Madhya Pradesh) — on the Ken river, a tiger reserve too; UNESCO network 2020. MP also has Pachmarhi and shares Achanakmar-Amarkantak with Chhattisgarh.
• Manas (Assam) — on the Bhutan border; also a UNESCO World Heritage Site and tiger reserve; home of the pygmy hog and golden langur. Assam's other reserve: Dibru-Saikhowa.
• 12 Indian reserves were on UNESCO's world network at the exam. As of 2026: the Cold Desert (Himachal Pradesh) reserve was added in 2025, making 13.
Also asked from this topic: the biosphere reserve located in Madhya Pradesh (Panna); the UNESCO programme behind biosphere reserves (MAB); India's first cold desert biosphere reserve (Spiti-Lahaul, Himachal Pradesh).

Modern History (1)

Swadeshi, Revolutionaries and Home Rule · HRA, HSRA, Bhagat Singh and Kakori

Q42. Hindustan Socialist Republican Association (HSRA) was founded in 1928 in which of the following cities?

  1. (a) Calcutta
  2. (b) Lahore
  3. (c) Pune
  4. (d) Delhi
Answer & solution

Answer: (d) Delhi

Answer: Option 4 — Delhi
The Hindustan Socialist Republican Association was founded at a meeting in the Feroz Shah Kotla ground, Delhi, in September 1928.
It reorganised the older Hindustan Republican Association (HRA) and added socialism to its aims.
Revision note — HRA, HSRA and Bhagat Singh
• HRA — founded 1924 at Kanpur by Sachindra Nath Sanyal, Jogesh Chandra Chatterjee and others; Ram Prasad Bismil was a key leader.
• Kakori train robbery — 9 August 1925, by the HRA; Bismil, Ashfaqullah Khan, Rajendra Lahiri and Roshan Singh were hanged.
• HSRA — 1928, Delhi; leaders Chandra Shekhar Azad (commander), Bhagat Singh, Sukhdev, Bhagwati Charan Vohra.
• Saunders killing — December 1928, Lahore, to avenge Lala Lajpat Rai's death after the Simon Commission lathi-charge.
• Central Legislative Assembly bomb — 8 April 1929, by Bhagat Singh and B.K. Dutt ("to make the deaf hear").
• Bhagat Singh, Sukhdev and Rajguru were hanged on 23 March 1931 at Lahore; Azad died at Alfred Park, Allahabad, on 27 February 1931.
Do not mix these up
• HRA vs HSRA — HRA: 1924, Kanpur, Kakori; HSRA: 1928, Delhi, Saunders and the Assembly bomb.
Also asked from this topic: the HSRA co-founder who bombed the Assembly with B.K. Dutt (Bhagat Singh); the year the HRA was formed (1924); the group behind the Kakori train robbery (HRA).

Medieval History (1)

Delhi Sultanate · Sultanate administration and iqta system

Q43. In Delhi Sultanate, the holder of an ‘iqta’, who also worked as the administrative head of his ‘iqta’, was designated as ________.

  1. (a) wazir
  2. (b) qazi
  3. (c) muqti
  4. (d) ariz
Answer & solution

Answer: (c) muqti

Answer: Option 3 — muqti
The holder of an iqta (a revenue assignment given in place of salary) was called the muqti or iqtadar.
He collected the iqta's revenue, paid his soldiers from it, and ran its administration and law and order.
Revision note — Delhi Sultanate administration
• The iqta system was set up by Iltutmish (Mamluk / Slave dynasty).
• Iqtas were transferable and not hereditary at first; Firoz Shah Tughlaq made them hereditary.
• Alauddin Khalji and Muhammad bin Tughlaq kept a close check on muqtis through accountants and audits.
• Wazir — head of the finance department (Diwan-i-Wizarat).
• Ariz-i-Mumalik — head of the military department (Diwan-i-Arz, set up by Balban).
• Qazi — judge who administered Islamic law (Sharia); Sadr looked after religious affairs.
• Village-level functionaries: khut, muqaddam (headmen) and patwari (accountant).
Do not mix these up
• Muqti vs mansabdar — muqti belongs to the Sultanate's iqta system; mansabdar belongs to the Mughal mansab system.
Also asked from this topic: the main duty of muqtis in their iqtas (to lead military campaigns and maintain law and order); the dynasty that introduced the iqta system (Mamluk dynasty).
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