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EMRS PGT study materials
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EMRS PGT practice questions

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Question 1Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII English (core) lesson on persuasive writing, a teacher explains that the phrase 'the pen is mightier than the sword' is an example of which rhetorical device?

  1. Synecdoche
  2. Hyperbole
  3. Onomatopoeia
  4. Metonymy Correct answer.

Explanation

Metonymy substitutes the name of an object with something closely associated with it: 'pen' stands for writing or diplomacy and 'sword' for armed force. The association is conceptual rather than a literal part-whole relation, so metonymy is the precise term here.

Question 2Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

While teaching the chapter on sets in the EMRS senior secondary mathematics syllabus, a teacher asks: which of the following is the power set of the set A = {2, 5}?

  1. {∅, {2}, {5}, {2, 5}} Correct answer.
  2. {{2, 5}}
  3. {{2}, {5}}
  4. {∅, {2, 5}}

Explanation

The power set P(A) is the collection of all subsets of A, including the empty set and A itself. For a two-element set this yields four subsets: ∅, {2}, {5} and {2, 5}, so the power set has 2² = 4 members.

Question 3Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A student in a Class XI physics class is told that a body moves along a straight line with uniform acceleration. Which of the following kinematic equations correctly relates velocity, acceleration and displacement for such motion?

  1. v = u + at
  2. v² = u² + 2as Correct answer.
  3. v = u + 2as
  4. s = ut + ½at²

Explanation

The third kinematic equation, v² = u² + 2as, directly relates initial velocity u, final velocity v, acceleration a and displacement s without involving time. It is derived by eliminating t between the first two equations.

Question 4Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XI chemistry lesson on the periodic table, a teacher notes that atomic radius generally decreases across a period from left to right. Which explanation correctly accounts for this trend?

  1. Electron-electron repulsion in the outer shell becomes dominant and compresses the atom.
  2. The number of shells increases steadily across the period, drawing electrons inward.
  3. Shielding by inner electrons increases faster than nuclear charge across the period.
  4. Nuclear charge increases while electrons enter the same shell, so the effective nuclear pull on outer electrons grows. Correct answer.

Explanation

Across a period, protons are added to the nucleus while electrons fill the same principal shell, so effective nuclear charge rises and the outer electrons are pulled closer. The result is a gradual decrease in atomic radius from left to right.

Question 5Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII biology teacher asks students to identify the site of the light-dependent reactions of photosynthesis in a chloroplast. Which structural feature correctly hosts these reactions?

  1. Stroma
  2. Thylakoid membrane Correct answer.
  3. Outer chloroplast envelope
  4. Intermembrane space

Explanation

The light-dependent reactions occur on the thylakoid membranes, where photosystems I and II, the electron transport chain and ATP synthase are embedded. These membranes harvest light energy and generate ATP and NADPH for the Calvin cycle.

Question 6Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

An economics teacher in a senior secondary class discusses a market where a single seller controls the entire supply of a good with no close substitutes. Such a market structure is best described as which of the following?

  1. Monopolistic competition
  2. Perfect competition
  3. Oligopoly
  4. Monopoly Correct answer.

Explanation

A monopoly exists when one firm is the sole supplier of a product with no close substitutes, giving the seller substantial price-setting power. Barriers to entry prevent other firms from entering and eroding that position.

Question 7Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A history teacher discussing the Indian freedom struggle mentions the Rowlatt Act of 1919. Which statement correctly describes its key provision?

  1. It allowed detention of political prisoners without trial for up to two years. Correct answer.
  2. It partitioned Bengal into two separate provinces.
  3. It granted Indians the right to elect members to provincial legislatures.
  4. It abolished the zamindari system in the provinces.

Explanation

The Rowlatt Act empowered the government to detain political prisoners without trial for up to two years, earning it the name 'Black Act'. Gandhi launched a nationwide hartal against it in 1919, which led to the Jallianwala Bagh tragedy.

Question 8Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII geography class on India's physiography, a teacher asks which of the following rivers is a west-flowing river that drains into the Arabian Sea?

  1. Narmada Correct answer.
  2. Krishna
  3. Mahanadi
  4. Godavari

Explanation

The Narmada flows westward through a rift valley between the Vindhya and Satpura ranges and empties into the Arabian Sea. Most peninsular rivers, by contrast, flow eastward into the Bay of Bengal.

Question 9Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A commerce teacher explains that a company issues shares at a price above their face value. The excess amount received over the face value is credited to which account?

  1. Calls in arrears
  2. Share forfeiture
  3. Securities premium Correct answer.
  4. Capital reserve

Explanation

When shares are issued above face value, the excess is credited to the securities premium account, which is a capital receipt. It can be used only for specified purposes such as issuing fully paid bonus shares or writing off preliminary expenses.

Question 10Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XI computer science lesson, a student writes the Python expression 7 // 2. Which value does this expression evaluate to?

  1. 4
  2. 3 Correct answer.
  3. 1
  4. 3.5

Explanation

In Python, the // operator performs floor division, returning the quotient rounded down to the nearest integer. For positive integers 7 and 2, the quotient is 3.5, and the floor is 3.

Question 11Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII English teacher discusses a poem in which the speaker addresses a skylark as a 'blithe spirit' and contrasts its joy with human sorrow. Which poet wrote this work?

  1. Percy Bysshe Shelley Correct answer.
  2. S. T. Coleridge
  3. John Keats
  4. William Wordsworth

Explanation

'To a Skylark' is a lyric by Percy Bysshe Shelley that celebrates the bird as a 'blithe spirit' and contrasts its untroubled joy with the sorrow of human existence. The poem is a well-known Romantic ode.

Question 12Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII mathematics lesson on differentiation, a teacher asks for the derivative of f(x) = sin(x²) with respect to x. Which expression is correct?

  1. 2x sin(x²)
  2. cos(2x)
  3. 2x cos(x²) Correct answer.
  4. cos(x²)

Explanation

The chain rule is applied here: differentiate the outer sine function to get cos(x²), then multiply by the derivative of the inner function x², which is 2x. The result is 2x cos(x²).

Question 13Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII chemistry teacher describes a reaction in which an alkyl halide reacts with aqueous potassium hydroxide to form an alcohol. This reaction is best classified as which type?

  1. Free radical substitution
  2. Elimination
  3. Electrophilic addition
  4. Nucleophilic substitution Correct answer.

Explanation

Hydroxide ion acts as a nucleophile and replaces the halide ion on the alkyl carbon, so the transformation is a nucleophilic substitution. With aqueous KOH, substitution to an alcohol is favoured over elimination.

Question 14Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII biology lesson on genetics, a teacher crosses a heterozygous tall pea plant (Tt) with a homozygous dwarf plant (tt). What phenotypic ratio is expected in the offspring?

  1. 3 tall : 1 dwarf
  2. 1 tall : 1 dwarf Correct answer.
  3. All tall
  4. 1 tall : 3 dwarf

Explanation

The Tt parent produces T and t gametes in equal proportion, while the tt parent produces only t gametes. The offspring are therefore half Tt (tall) and half tt (dwarf), giving a 1:1 phenotypic ratio.

Question 15Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII economics teacher explains that a government increases spending to boost aggregate demand during a recession. This policy action is an example of which of the following?

  1. Contractionary monetary policy
  2. Expansionary monetary policy
  3. Expansionary fiscal policy Correct answer.
  4. Contractionary fiscal policy

Explanation

Government spending and taxation are instruments of fiscal policy, and raising spending to stimulate demand is expansionary fiscal policy. Monetary policy, by contrast, is conducted by the central bank through money supply and interest rates.

Question 16Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII computer science lesson on relational databases, a teacher asks which SQL clause is used to filter rows returned by a query based on a condition. Which clause is correct?

  1. HAVING
  2. GROUP BY
  3. WHERE Correct answer.
  4. ORDER BY

Explanation

The WHERE clause applies a condition to individual rows before grouping, so only rows satisfying the condition are returned. It is the standard row-level filter in a SELECT statement.

Question 17Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XI physics teacher asks students to identify the SI unit of magnetic flux. Which of the following is the correct unit?

  1. Weber Correct answer.
  2. Henry
  3. Tesla
  4. Farad

Explanation

Magnetic flux is measured in webers, where one weber equals one tesla multiplied by one square metre. It represents the total magnetic field passing through a given area.

Question 18Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A history teacher discusses the Harappan civilisation and asks which feature best indicates that its cities were planned. Which option correctly identifies such a feature?

  1. Palaces were built on high platforms overlooking the city.
  2. Iron tools were widely used in agriculture.
  3. Streets were laid out on a grid pattern with covered drainage. Correct answer.
  4. Cities were surrounded by stone fortification walls only.

Explanation

Harappan cities such as Mohenjo-daro and Harappa show a grid layout of streets with an elaborate covered drainage system, which is the clearest evidence of urban planning. Houses were built with standardised burnt bricks along these streets.

Question 19Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII geography teacher asks students to identify the type of farming in which a single crop is grown on a large area primarily for sale. Which term correctly describes this practice?

  1. Intensive subsistence farming
  2. Shifting cultivation
  3. Commercial farming Correct answer.
  4. Subsistence farming

Explanation

Commercial farming is characterised by large-scale cultivation of a single crop for sale in the market rather than for the farmer's own consumption. It typically uses modern inputs such as machinery, fertilisers and pesticides.

Question 20Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII commerce lesson on partnership accounts, a teacher explains that when a new partner is admitted, the existing partners may sacrifice a share of profit. What is the share given up by the old partners called?

  1. Profit-sharing ratio
  2. Gaining ratio
  3. Capital ratio
  4. Sacrificing ratio Correct answer.

Explanation

The sacrificing ratio is the proportion of profit that existing partners surrender in favour of an incoming partner. It is calculated as the old profit-sharing ratio minus the new profit-sharing ratio for each old partner.

Question 21Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII English teacher asks students to identify the figure of speech in the line 'The wind whispered through the trees.' Which option correctly names it?

  1. Oxymoron
  2. Simile
  3. Personification Correct answer.
  4. Metaphor

Explanation

Personification attributes human qualities or actions to non-human things; here the wind is said to 'whisper', which is a human action. The line does not compare two things explicitly or implicitly in the way a simile or metaphor does.

Question 22Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII mathematics class on probability, a teacher asks for the probability that a fair die shows an even number when rolled once. Which value is correct?

  1. 1/2 Correct answer.
  2. 1/6
  3. 2/3
  4. 1/3

Explanation

A fair die has six equally likely outcomes, and the even numbers are 2, 4 and 6, giving three favourable outcomes. The probability is therefore 3/6, which simplifies to 1/2.

Question 23Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII biology teacher explains that a particular genetic disorder is caused by the presence of an extra copy of chromosome 21. Which condition is described?

  1. Turner's syndrome
  2. Klinefelter's syndrome
  3. Down's syndrome Correct answer.
  4. Haemophilia

Explanation

Down's syndrome results from trisomy of chromosome 21, giving 47 chromosomes instead of 46. It is associated with intellectual disability and characteristic facial features.

Question 24Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII physics teacher discusses electromagnetic induction and asks which law states that the induced emf is proportional to the rate of change of magnetic flux. Which law is correct?

  1. Faraday's law Correct answer.
  2. Lenz's law
  3. Coulomb's law
  4. Ampere's circuital law

Explanation

Faraday's law of electromagnetic induction states that the induced emf equals the negative rate of change of magnetic flux through a circuit. The negative sign reflects Lenz's law, which fixes the direction of the induced current.

Question 25Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII chemistry lesson on electrochemistry, a teacher asks which of the following statements about the standard hydrogen electrode is correct.

  1. Its potential varies with the nature of the metal used.
  2. It uses a silver electrode dipped in silver nitrate solution.
  3. It operates only in strongly alkaline conditions.
  4. Its standard electrode potential is arbitrarily fixed at zero volts. Correct answer.

Explanation

By convention, the standard hydrogen electrode is assigned a potential of 0.00 V at 298 K, 1 bar hydrogen pressure and unit hydrogen ion activity. All other electrode potentials are measured relative to this reference.

Question 26Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII English lesson on John Keats, a teacher explains the concept of 'negative capability'. Which description best captures what Keats meant by this phrase?

  1. The power to create vivid sensory imagery that appeals to more than one sense at once
  2. The ability to write in the negative form so that assertions are implied rather than stated
  3. The tendency to end a poem with a question that leaves the reader unsettled
  4. The capacity to remain in uncertainties and doubts without irritably reaching after fact and reason Correct answer.

Explanation

Keats used the phrase in a letter of 1817 to describe the quality that forms a man of achievement, especially in literature: the ability to stay in half-knowledge and mystery without impatiently demanding resolution. It is a temperament of the poet, not a device of imagery or syntax, and it is contrasted with the 'irritable reaching after fact and reason' of writers such as Coleridge.

Question 27Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII English teacher discusses the narrative technique of Virginia Woolf's novels. Which feature is most characteristic of her stream-of-consciousness method?

  1. Direct addresses to the reader that interrupt the story to comment on its morality
  2. A chain of external events narrated in strict chronological order by an omniscient observer
  3. The uninterrupted flow of a character's inner impressions, memories and associations Correct answer.
  4. A frame narrative in which several characters each tell a separate tale in turn

Explanation

Stream of consciousness renders the continuous, associative movement of a character's mind, where sensations, memories and half-formed thoughts blend without the ordering logic of external plot. Woolf uses this in novels such as Mrs Dalloway and To the Lighthouse, where the action is slight but the inner life is dense.

Question 28Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII English poetry class, a teacher explains the Petrarchan sonnet form. Which rhyme scheme and structural division correctly describe it?

  1. An octave rhyming abbaabba followed by a sestet with a variable rhyme scheme Correct answer.
  2. Four tercets and a closing couplet, rhyming aba bcb cdc ded ee
  3. Continuous rhyme in a single eighteen-line stanza without division
  4. Three quatrains and a couplet, rhyming abab cdcd efef gg

Explanation

The Petrarchan or Italian sonnet divides into an octave, rhyming abbaabba, and a sestet whose rhyme scheme varies, commonly cdecde or cdcdcd. The turn or volta usually falls between the two parts, shifting the argument or mood.

Question 29Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII English teacher asks students to identify the type of clause underlined in a complex sentence of an unseen passage. The clause 'because the monsoon arrived early' in the sentence 'The farmers harvested the crop early because the monsoon arrived early' is best described as which kind of clause?

  1. A noun clause functioning as the object of the verb
  2. A relative clause modifying the noun 'crop'
  3. An adverbial clause of reason modifying the main verb Correct answer.
  4. A coordinate clause joined by a coordinating conjunction

Explanation

The clause is introduced by the subordinating conjunction 'because' and answers the question why the harvesting happened, so it functions adverbially, modifying the verb 'harvested'. It cannot stand alone and is subordinate to the main clause.

Question 30Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII English prose lesson on Francis Bacon's essays, a teacher quotes the aphoristic style. Which feature best characterises Bacon's sentences in the Essays?

  1. Long periodic sentences with elaborate subordinate clauses and classical allusions
  2. Terse, weighty statements packed with compressed maxims and balanced contrasts Correct answer.
  3. Extended lyrical passages dwelling on personal emotion and nature
  4. Colloquial dialogue interspersed with regional dialect forms

Explanation

Bacon's essays are famous for their brevity and density, presenting practical wisdom in short, pointed sentences often built on antithesis, as in 'Reading maketh a full man'. The style is impersonal and utilitarian rather than lyrical or conversational.

Question 31Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII mathematics teacher asks students to evaluate the definite integral of x·e^x with respect to x from 0 to 1. Which value is correct?

  1. e − 1
  2. 2e − 1
  3. 1 Correct answer.
  4. e

Explanation

Integrating by parts with u = x and dv = e^x dx gives x·e^x − e^x, that is e^x(x − 1). Evaluating from 0 to 1 gives (1·0) − (0 − 1) = 1. The definite integral therefore equals 1.

Question 32Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII mathematics lesson on matrices, a teacher states that a square matrix A satisfies A² = A. Which property must such a matrix necessarily have?

  1. It must be invertible with inverse equal to itself
  2. It must be skew-symmetric
  3. It must be a scalar multiple of the identity matrix
  4. Its eigenvalues can only be 0 or 1 Correct answer.

Explanation

An idempotent matrix satisfies A² = A, so its minimal polynomial divides λ² − λ = λ(λ − 1). Every eigenvalue must therefore be a root of that polynomial, leaving only 0 and 1 as possible eigenvalues.

Question 33Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII mathematics teacher asks for the number of onto functions from a set of 4 elements to a set of 2 elements. Which count is correct?

  1. 8
  2. 16
  3. 14 Correct answer.
  4. 6

Explanation

The number of onto functions from a set of m elements to a set of n elements is given by inclusion–exclusion. Here it is 2⁴ − 2·1⁴ = 16 − 2 = 14. Equivalently, each of the four elements chooses one of two images, and the two all-same assignments are excluded.

Question 34Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII mathematics class on vectors, a teacher gives two vectors a and b with |a| = 3, |b| = 4 and a·b = 6. What is the magnitude of the vector product a × b?

  1. 6
  2. 12
  3. 18
  4. 6√3 Correct answer.

Explanation

Since a·b = |a||b|cosθ = 6, we get cosθ = 6/12 = 1/2, so sinθ = √3/2. The magnitude of the cross product is |a||b|sinθ = 12 × √3/2 = 6√3.

Question 35Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII physics teacher explains the photoelectric effect. Which observation directly contradicts the classical wave prediction and supports the photon model?

  1. The maximum kinetic energy of emitted electrons depends on frequency but not on intensity Correct answer.
  2. The stopping potential varies with the nature of the cathode material
  3. The photocurrent increases when the intensity of incident light increases
  4. Emission of electrons begins only after a measurable time lag at low intensity

Explanation

Classically, brighter light carries more energy and should eject faster electrons, so kinetic energy should rise with intensity. Experiment shows instead that maximum kinetic energy depends on frequency and is independent of intensity, which the photon model explains through E = hν − φ.

Question 36Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII physics lesson on optics, a teacher describes a compound microscope in normal adjustment. Which statement about the final image is correct?

  1. The final image is real, inverted and formed at the near point
  2. The final image is virtual, inverted and formed at infinity Correct answer.
  3. The final image is virtual, erect and formed between the lenses
  4. The final image is real, erect and formed at the far point

Explanation

In a compound microscope the objective forms a real, inverted intermediate image inside the focal length of the eyepiece. The eyepiece then acts as a magnifier, producing a virtual, magnified and inverted final image, which in normal adjustment lies at infinity for relaxed viewing.

Question 37Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII physics teacher discusses the de Broglie hypothesis. If the kinetic energy of an electron is increased to four times its initial value, by what factor does its de Broglie wavelength change?

  1. It becomes four times larger
  2. It becomes one half of the original Correct answer.
  3. It becomes twice the original
  4. It becomes one quarter of the original

Explanation

The de Broglie wavelength is λ = h/p, and for a given mass p = √(2mK). Quadrupling the kinetic energy doubles the momentum, so the wavelength is halved.

Question 38Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII chemistry lesson on coordination compounds, a teacher asks students to apply crystal field theory to the [Fe(CN)₆]³⁻ ion. Which statement is correct?

  1. It is high spin with five unpaired electrons because the complex is octahedral
  2. It is low spin with three unpaired electrons because iron is in the +2 state
  3. It is low spin with one unpaired electron because cyanide is a strong-field ligand Correct answer.
  4. It is high spin with four unpaired electrons because cyanide is a weak-field ligand

Explanation

In [Fe(CN)₆]³⁻, iron is in the +3 state with a d⁵ configuration. Cyanide produces a large crystal field splitting, so the t2g level is filled before eg, giving t2g⁵ eg⁰ with a single unpaired electron and low spin.

Question 39Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII chemistry teacher discusses the reaction of an aldehyde with a Grignard reagent followed by acidic hydrolysis. What is the product when ethanal reacts with methylmagnesium bromide and the mixture is then hydrolysed?

  1. Ethanol
  2. Butan-2-ol
  3. Propan-2-ol Correct answer.
  4. Propan-1-ol

Explanation

The Grignard reagent adds its methyl group to the carbonyl carbon of ethanal, giving an alkoxide that on hydrolysis yields a secondary alcohol with one more carbon than the aldehyde. Ethanal (two carbons) plus one methyl carbon gives propan-2-ol.

Question 40Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII chemistry lesson on chemical kinetics, a teacher states that a reaction is first order with respect to a reactant. Which graph, for that reactant, should be a straight line?

  1. Natural logarithm of concentration against time Correct answer.
  2. Concentration squared against time
  3. Concentration against time
  4. Reciprocal of concentration against time

Explanation

For a first-order process, the integrated rate law is ln[A] = ln[A]₀ − kt, which is linear in time with slope −k. Plotting the natural logarithm of concentration against time therefore gives a straight line.

Question 41Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII chemistry teacher explains the acidic strength of substituted phenols. Which substituent on the benzene ring increases the acidity of phenol most strongly?

  1. A methyl group at the para position
  2. An amino group at the para position
  3. A methoxy group at the para position
  4. A nitro group at the para position Correct answer.

Explanation

The nitro group is strongly electron-withdrawing by both inductive and resonance effects, dispersing the negative charge on the phenoxide ion and stabilising it. Greater stability of the conjugate base means a stronger acid, so p-nitrophenol is far more acidic than phenol.

Question 42Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII biology lesson on molecular genetics, a teacher asks about the role of the lac operon's repressor. Under which condition does the repressor bind the operator most effectively?

  1. When glucose is absent regardless of lactose
  2. When both lactose and glucose are absent
  3. When lactose is absent and glucose is plentiful Correct answer.
  4. When lactose is present and glucose is absent

Explanation

The lac repressor is active when it is not bound to an inducer. Lactose (via allolactose) acts as the inducer and inactivates the repressor, so the repressor binds the operator most effectively when lactose is scarce, as in the presence of plentiful glucose and no lactose.

Question 43Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII biology teacher explains the structure of the human nephron. In which part of the nephron does the bulk of glucose reabsorption occur?

  1. The proximal convoluted tubule Correct answer.
  2. The distal convoluted tubule
  3. The descending limb of the loop of Henle
  4. The collecting duct

Explanation

Glucose is reabsorbed almost completely in the proximal convoluted tubule, where the epithelial cells have abundant microvilli and sodium-linked cotransporters. Under normal blood glucose levels no glucose appears in the urine.

Question 44Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII biology lesson on biotechnology, a teacher describes the use of restriction endonucleases. Which statement about EcoRI is correct?

  1. It cuts DNA at random sites to produce blunt ends
  2. It joins DNA fragments by forming phosphodiester bonds
  3. It synthesises RNA from a DNA template
  4. It recognises the palindromic sequence GAATTC and produces sticky ends Correct answer.

Explanation

EcoRI recognises the palindromic hexanucleotide GAATTC and cuts between G and A, leaving single-stranded overhangs known as sticky ends. These ends allow complementary fragments to anneal and be ligated.

Question 45Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII biology teacher discusses plant hormones. Which response is chiefly controlled by auxin in phototropism of a coleoptile?

  1. Rapid cell division on the illuminated side caused by cytokinin
  2. Loss of turgor on the shaded side caused by abscisic acid
  3. Inhibition of growth on the shaded side caused by ethylene
  4. Cell elongation on the shaded side caused by lateral redistribution of auxin Correct answer.

Explanation

In phototropism, auxin redistributes laterally towards the shaded side of the coleoptile, where it promotes greater cell elongation. The uneven growth bends the tip towards light.

Question 46Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII history teacher discusses the Mauryan administration. Which official, according to Ashokan inscriptions and the Arthashastra tradition, was charged with moral supervision and the welfare of the people?

  1. Gahapati
  2. Amatya
  3. Senapati
  4. Dhamma mahamatta Correct answer.

Explanation

Ashoka created the office of dhamma mahamatta, officers whose duties included promoting dhamma, welfare work and the redress of grievances among the people. The term appears in the Ashokan edicts as a distinctive innovation of Mauryan administration.

Question 47Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII history lesson on colonial India, a teacher explains the significance of the Permanent Settlement of 1793. Which consequence followed most directly from it?

  1. The state share of revenue was made to vary each year with the harvest
  2. Revenue collection was handed over to village panchayats
  3. Cultivators were granted direct ownership of the land they tilled
  4. Zamindars became the recognised proprietors of land in return for a fixed revenue Correct answer.

Explanation

Under the Permanent Settlement, introduced by Cornwallis in Bengal in 1793, zamindars were recognised as proprietors who paid a fixed revenue to the Company. The state's income was stabilised, but cultivators were left dependent on zamindars.

Question 48Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII history teacher discusses the Indian national movement and the split of 1907 at Surat. Which issue was the immediate cause of the confrontation between the Moderates and the Extremists?

  1. The choice of the Congress session's president and the demand for swaraj Correct answer.
  2. The question of separate electorates for minorities
  3. The decision to boycott the Simon Commission
  4. The proposal to support the British in the First World War

Explanation

At Surat in 1907 the Extremists objected to the nomination of Rash Behari Ghosh as president and pressed for swaraj as the goal of the Congress. The dispute over the presidency and the goal split the party until the Lucknow reunion of 1916.

Question 49Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

In a Class XII geography lesson on India's climate, a teacher explains the mechanism of the Indian monsoon. Which factor is most directly responsible for the reversal of pressure patterns between summer and winter?

  1. The seasonal migration of the ITCZ and differential heating of land and sea Correct answer.
  2. The presence of the Himalayas as a barrier to cold winds
  3. The rotation of the earth on its axis
  4. The distribution of ocean currents in the Indian Ocean

Explanation

The differential heating of the Asian landmass and the Indian Ocean, together with the northward shift of the ITCZ in summer, reverses the pressure gradient. This draws moist air from the ocean onto the land in summer and reverses the flow in winter.

Question 50Subject concerned (PGT post subject, e.g. English, Hindi, Maths, Physics, Chemistry, Biology, Economics, History, Geography, Commerce, Computer Science)

A Class XII geography teacher asks students to identify a characteristic feature of the Deccan Plateau. Which statement is correct?

  1. It is a basaltic lava plateau formed by volcanic eruptions in the Cretaceous period Correct answer.
  2. It is composed mainly of alluvial soil deposited by Himalayan rivers
  3. It is a folded mountain range formed by the collision of plates
  4. It is a coastal plain formed by wave action

Explanation

The Deccan Plateau is built of Deccan Traps, basalt laid down by extensive fissure eruptions around the end of the Cretaceous. The weathering of this basalt gives rise to black regur soil, well suited to cotton.