Q&A: practice questions with answers

Concept: Kudremukh ('horse-face' peak) in Chikkamagaluru district, Karnataka, lies in the Western Ghats and holds magnetite iron ore.

1. Kudremukh Iron Ore Company Ltd (KIOCL) mined and pelletised ore here; mining stopped in 2006 for the Kudremukh National Park.
2. Other Karnataka iron belts: Bellary–Hospet, Baba Budan hills.
3. Manganese → Sandur/Odisha; bauxite → Odisha; copper → Khetri, Malanjkhand.

Yaad rakhein: Kudremukh – KIOCL – iron ore slurry piped to Mangaluru port.

Answer: (D) Iron Ore

Concept: The SDG Index is published in the Sustainable Development Report of the UN Sustainable Development Solutions Network (SDSN).

1. In SDG Index 2025, India scored 67.0 and entered the top 100 for the first time (rank 99 of 167).
2. Finland topped the index; India was 109th in 2024.

Yaad rakhein: SDR 2025: India – score 67, rank 99 (first time in top 100).

Answer: (C) 67.0

Concept: Article 323A (inserted by the 42nd Amendment, 1976) allows Parliament to set up administrative tribunals for service matters.

1. Parliament passed the Administrative Tribunals Act, 1985.
2. The Central Administrative Tribunal (CAT) was set up on 1 November 1985; Principal Bench at New Delhi.
3. 1976 is the year of the enabling amendment, not of CAT.

Yaad rakhein: 42nd Amendment (1976) → Article 323A → CAT (1985).

Answer: (A) 1985

Concept: Wind both erodes (deflation, abrasion) and deposits (sand dunes, loess) in deserts.

1. A barchan is a crescent-shaped sand dune with horns pointing downwind – a depositional feature.
2. Yardang (ridge carved in rock) and inselberg (isolated residual hill) are erosional features.
3. Moraine is debris deposited by a glacier, not wind.

Trick: Wind deposits = dunes (barchan, seif) + loess; wind erodes = yardang, zeugen, mushroom rock.

Answer: (B) Barchan

Concept: CPU power use rises steeply with clock frequency and voltage, so the cheapest way to save energy is to slow the processor.

1. The Power Saver plan lowers the 'Maximum processor state' (e.g. to 50–70%), capping clock speed and heat.
2. Lower frequency → less power and heat, but programs run slower – the drop in responsiveness.
3. The GPU is not disabled, cache is not flushed, and the disk is spun down sooner (not later) to save power.

Trick: Power Saver = lower CPU frequency (throttling); High Performance = 100% processor state.

Answer: (D) Reducing the maximum processor state (clock speed/frequency) to cap the peak computational capacity and thermal output

Concept: The Preamble promises Justice – social, economic and political; this ideal of justice is borrowed from the Russian Revolution (1917).

1. Russian (1917) → Justice: social, economic and political.
2. French Revolution (1789) → Liberty, Equality, Fraternity (tempting option, but a different phrase).
3. Republic is from France; Five-Year Plans/Fundamental Duties from the USSR.

Yaad rakhein: Justice → Russia; Liberty-Equality-Fraternity → France.

Answer: (C) Russian Revolution

Concept: Dr. L. Subramaniam is a Carnatic and fusion violinist known for blending Indian and Western classical music.

1. His fusion album 'Fantasy Without Limits' (1980) – listed in option (A) as 'Fantasy With Truth' – earned him a Grammy nomination in 1981.
2. 'West Meets East' is the Ravi Shankar–Yehudi Menuhin album series, not his.

Yaad rakhein: L. Subramaniam – violin – 'Fantasy' album – Grammy nomination 1981.

Answer: (A) Fantasy With Truth

Concept: The World Economic Forum (founded 1971 by Klaus Schwab, HQ Geneva) holds its Annual Meeting every January in the Swiss Alps.

1. The 55th Annual Meeting was held at Davos-Klosters, Switzerland, on 20–24 January 2025.
2. Theme: 'Collaboration for the Intelligent Age'.

Yaad rakhein: WEF annual meet = Davos (Switzerland) every January.

Answer: (D) Davos-Klosters, Switzerland

Concept: After the Mauryas, Kalinga (Odisha) rose under the Chedi or Mahameghavahana dynasty.

1. Kharavela (1st century BCE) was its greatest ruler; his deeds are recorded in the Hathigumpha inscription at Udayagiri near Bhubaneswar.
2. He was a patron of Jainism.
3. Kanishka – Kushana; Pushyamitra – Shunga; Gautamiputra Satakarni – Satavahana.

Yaad rakhein: Kharavela – Kalinga – Hathigumpha – Jain.

Answer: (D) Kharavela

Concept: Electric charge is measured in coulomb (C); charge $Q=I\times t$.

1. $1\text{C}=1\text{A}\times 1\text{s}$: the charge carried by a 1 A current in 1 s.
2. Ampere is the unit of current (rate of flow of charge), volt of potential difference, ohm of resistance.

Yaad rakhein: Charge – coulomb; current – ampere; 1 C ≈ $6.25\times {10}^{18}$ electrons.

Answer: (A) Coulomb

Concept: Average elevation of a continent includes the ice covering its land.

1. Antarctica's ice sheet is about 2 km thick on average, giving it an average elevation of about 2,300–2,500 m – the highest of all continents.
2. Asia comes second (about 900–1,000 m) despite having Everest.

Yaad rakhein: Highest average elevation – Antarctica; highest peak – Asia.

Answer: (C) Antarctica

Concept: A microcontroller is a 'computer on a single chip'.

1. It packs CPU, RAM/ROM (flash) and I/O ports, timers etc. into one compact IC – used in washing machines, remotes, cars.
2. A motherboard only connects separate components; a system bus is the data path between them.

Trick: Microprocessor = only CPU; Microcontroller = CPU + memory + I/O on one chip.

Answer: (A) Microcontroller

Concept: RBI Governors are appointed by the Central Government.

1. Sanjay Malhotra, an IAS officer (Rajasthan cadre, 1990) and former Revenue Secretary, became the 26th Governor on 11 December 2024.
2. He succeeded Shaktikanta Das (25th Governor).
3. Michael Patra and Poonam Gupta are/were Deputy Governors; Raghuram Rajan was the 23rd Governor.

Yaad rakhein: 25th – Shaktikanta Das, 26th – Sanjay Malhotra (Dec 2024).

Answer: (D) Sanjay Malhotra

Concept: The Pushyabhutis (Vardhanas) of Thanesar rose to power in the late 6th century CE.

1. Prabhakarvardhana, the first major ruler, took the title Maharajadhiraja and fought the Hunas in the north-west.
2. Banabhatta's Harshacharita calls him 'Huna-harina-kesari' – a lion to the Huna deer.
3. Rajyavardhana and Harshavardhana were his sons; Harsha is famed for his later empire.

Yaad rakhein: Huna-harina-kesari = Prabhakarvardhana (father of Harsha).

Answer: (B) Prabhakarvardhana

Concept: Economic activities are grouped by what they do with resources.

1. Primary: taking from nature (farming, mining). Secondary: manufacturing – turning raw material into goods.
2. Cotton textiles (cotton → cloth) and iron & steel (ore → steel) are manufacturing, hence secondary.
3. Tertiary = services; quaternary = knowledge/IT services.

Trick: Factory/processing = secondary sector (industrial sector).

Answer: (D) Secondary sector

Concept: A number is divisible by 11 if (sum of digits at odd places) − (sum of digits at even places) is 0 or a multiple of 11.

1. 978626: odd places $9+8+2=19$, even places $7+6+6=19$.
2. Difference $=19-19=0$ ⇒ divisible by 11.
3. Check 869756: $8+9+5=22$, $6+7+6=19$, difference $3$ ⇒ not divisible.

Trick: Just take the alternate-digit sums; a difference of 0, 11, 22… means divisible.

Answer: (B) 978626

Concept: Take the smaller power common: $6^x-6^{x-1}=6^{x-1}(6-1)$.

1. $6^{x-1}\times 5=30\Rightarrow 6^{x-1}=6=6^1$.
2. So $x-1=1\Rightarrow x=2$.
3. $\frac{2x-1}{2x+3}=\frac{4-1}{4+3}=\frac{3}{7}$.

Trick: Try $x=2$ directly: $36-6=30$ ✓.

Answer: (A) $\frac{3}{7}$

Concept: $\text{SI}=\frac{P\times R\times T}{100}\Rightarrow P=\frac{\text{SI}\times 100}{R\times T}$.

1. SI = ₹1320, $R=16\%$, $T=3$ years.
2. $P=\frac{1320\times 100}{16\times 3}=\frac{132000}{48}$.
3. $P=2750$.

Trick: Total rate $=16\times 3=48\%$; $48\%$ of P = 1320 ⇒ $1\%=27.5$ ⇒ $P=2750$.

Answer: (D) ₹2,750

Concept: Given sum and difference: larger $=\frac{\text{sum}+\text{difference}}{2}$.

1. $M+D=52$, $M-D=24$.
2. Adding: $2M=76\Rightarrow M=38$.
3. Daughter $=52-38=14$ (check: $38-14=24$ ✓).

Trick: Larger number $=\frac{52+24}{2}$, smaller $=\frac{52-24}{2}$.

Answer: (C) 38

Concept: Third proportional of $a$ and $b$ is $\frac{b^2}{a}$.

1. For 36, 48: $\frac{{48}^2}{36}=\frac{2304}{36}=64$.
2. For 49, 64: $\frac{{64}^2}{49}=\frac{4096}{49}$.
3. Ratio $=64:\frac{4096}{49}=\frac{64\times 49}{4096}=\frac{49}{64}$, i.e. $49:64$.

Trick: $\frac{b_1^2/a_1}{b_2^2/a_2}$ — keep powers, cancel before multiplying.

Answer: (D) 49 : 64