I85PREP
⌘ K
NVS PGT study materials
NVS PGT study resources

NVS PGT practice questions

One question at a time. Build your NVS PGT understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Subject Knowledge (concerned teaching subject)

In a secondary school English class, a teacher wants learners to infer meaning of unfamiliar words from context. Which instructional strategy most directly develops this skill?

  1. Testing spelling of isolated words in a weekly dictation
  2. Requiring learners to copy dictionary definitions verbatim
  3. Asking learners to memorise a decontextualised word list each week
  4. Providing cloze passages where surrounding sentences signal the target word's meaning Correct answer.

Explanation

Contextual inference is developed when learners practise using surrounding syntactic and semantic clues to construct meaning. Cloze tasks with strong contextual signals give deliberate practice in exactly that reasoning. Memorisation, copying and spelling drills build other competencies, not inference.

Question 2Subject Knowledge (concerned teaching subject)

A mathematics teacher asks students to explain why the sum of two odd numbers is always even. Which level of the revised Bloom's taxonomy does this task primarily target?

  1. Remembering
  2. Creating
  3. Applying
  4. Understanding Correct answer.

Explanation

Explaining why a generalisation holds requires learners to construct meaning and justify reasoning, which is the understanding level. It goes beyond recalling a fact but does not require executing a procedure in a new situation or producing an original product.

Question 3Subject Knowledge (concerned teaching subject)

A science teacher plans a practical on photosynthesis and wants to assess process skills rather than factual recall. Which assessment task best serves this purpose?

  1. A labelled diagram of a chloroplast copied from the textbook
  2. A multiple-choice quiz on the balanced equation for photosynthesis
  3. A practical report analysing how light intensity affected bubble production in pondweed Correct answer.
  4. An oral recitation of the word equation for photosynthesis

Explanation

Process skills involve designing, measuring, recording and interpreting data from an investigation. A report analysing how a manipulated variable affected a measured response requires those skills directly. The other tasks assess recall or reproduction of given information.

Question 4Subject Knowledge (concerned teaching subject)

In a Hindi lesson, a teacher uses a poem with repeated refrain lines to build fluency. Which principle best explains why repeated reading of the refrain supports oral fluency?

  1. Repetition lowers the affective filter so learners need no feedback
  2. Repetition reduces the cognitive load of decoding, freeing attention for expression and meaning Correct answer.
  3. Repetition replaces the need for explicit vocabulary instruction entirely
  4. Repetition guarantees accurate pronunciation of every phoneme in the language

Explanation

Repeated reading automatises word recognition, so decoding demands fewer attentional resources and learners can attend to phrasing, intonation and meaning. It supports but does not guarantee pronunciation accuracy and does not remove the need for vocabulary teaching or feedback.

Question 5Subject Knowledge (concerned teaching subject)

A social science teacher wants to develop map-reading competence. Which activity most directly requires interpretation of scale?

  1. Listing the names of state capitals from memory
  2. Reciting the cardinal directions in order
  3. Calculating the actual distance between two towns using the map's scale bar Correct answer.
  4. Colouring political boundaries on an outline map

Explanation

Scale expresses the ratio between map distance and ground distance, so interpreting it means converting measured map lengths into real distances. Colouring, listing and reciting involve identification or recall rather than quantitative interpretation of scale.

Question 6Subject Knowledge (concerned teaching subject)

A physics teacher demonstrates that a heavier and a lighter ball dropped together from the same height land almost simultaneously in air. Which concept does this demonstration most directly illustrate?

  1. That gravitational acceleration is independent of mass in the absence of significant air resistance Correct answer.
  2. That gravitational force on an object is proportional to its volume
  3. That heavier objects always fall faster because they have more inertia
  4. That air resistance increases with the mass of a falling body

Explanation

Near Earth's surface all bodies accelerate at approximately the same rate under gravity when air resistance is negligible, so mass does not determine free-fall acceleration. The near-simultaneous landing illustrates this independence rather than a mass-dependent effect.

Question 7Subject Knowledge (concerned teaching subject)

In a biology class, students compare a plant cell and an animal cell. Which structural feature is present in the plant cell but absent in the animal cell?

  1. Cell membrane
  2. Cell wall Correct answer.
  3. Mitochondria
  4. Ribosomes

Explanation

Plant cells possess a rigid cellulose cell wall outside the plasma membrane, providing shape and structural support. Animal cells lack a cell wall, though they share ribosomes, a cell membrane and mitochondria with plant cells.

Question 8Subject Knowledge (concerned teaching subject)

A chemistry teacher asks learners to balance the equation for the combustion of methane. Which coefficient set correctly balances CH4 + O2 → CO2 + H2O?

  1. 1, 2, 1, 2 Correct answer.
  2. 1, 2, 2, 1
  3. 2, 2, 2, 2
  4. 1, 1, 1, 1

Explanation

Balancing requires equal numbers of each atom on both sides. With coefficients 1, 2, 1, 2 there are one carbon, four hydrogen and four oxygen atoms on each side, satisfying conservation of mass.

Question 9Subject Knowledge (concerned teaching subject)

A teacher wants to check whether learners can transfer a mathematical concept to an unfamiliar situation. Which question type is most appropriate?

  1. A recall question asking for the statement of the theorem
  2. A worked example identical to one done in class
  3. A true-or-false item on a definition
  4. A novel word problem requiring selection and combination of known procedures Correct answer.

Explanation

Transfer is demonstrated when a learner selects and applies prior knowledge in a context that differs from the original learning situation. A novel problem requiring procedural choice tests that adaptive application, whereas recall, repetition and definitions test recognition.

Question 10Subject Knowledge (concerned teaching subject)

In a history lesson, students examine two contrasting accounts of the same event. Which question best develops historical thinking?

  1. Which account was written first?
  2. How many paragraphs does each account contain?
  3. Why might the two authors have described the event differently? Correct answer.
  4. Which account uses longer sentences?

Explanation

Historical thinking involves evaluating sources for perspective, purpose and bias. Asking why authors differ prompts learners to consider the provenance and standpoint behind each account. The other questions concern chronology or surface features of text.

Question 11Subject Knowledge (concerned teaching subject)

A geography teacher introduces the concept of a river's long profile. Which description correctly matches the upper course?

  1. Flat gradient with extensive levees and deltas
  2. Uniform gradient with meanders and oxbow lakes
  3. Gentle gradient with wide floodplain and deposition dominant
  4. Steep gradient with vertical erosion and narrow valley Correct answer.

Explanation

The upper course is characterised by a steep gradient, dominant vertical erosion and a narrow V-shaped valley. Downstream, the gradient flattens and lateral erosion, meanders and deposition become more prominent.

Question 12Subject Knowledge (concerned teaching subject)

A teacher plans a group project and wants to ensure individual accountability. Which design element best achieves this?

  1. Letting the most able student complete the shared task
  2. Assigning one group grade to the whole team regardless of contribution
  3. Assigning distinct roles plus individual reflection on each member's contribution Correct answer.
  4. Allowing each group to submit a single anonymous report

Explanation

Individual accountability exists when each learner's contribution can be identified and assessed. Distinct roles combined with individual reflection make participation visible, whereas single shared products allow free-riding.

Question 13Subject Knowledge (concerned teaching subject)

In a language classroom, a teacher corrects every spoken error immediately during a fluency activity. What is the most likely effect?

  1. It disrupts the communicative flow and may raise learner anxiety Correct answer.
  2. It guarantees accurate pronunciation in later production
  3. It increases fluency by preventing fossilisation
  4. It eliminates the need for any later accuracy work

Explanation

Immediate correction during fluency tasks interrupts meaning-focused communication and can increase anxiety and reduce willingness to speak. Accuracy feedback is better placed in dedicated accuracy-focused stages or delayed until after the activity.

Question 14Subject Knowledge (concerned teaching subject)

A teacher uses an advance organiser before a new unit. What is the primary purpose of this device?

  1. To replace the need for formative assessment
  2. To test prior knowledge with a graded quiz
  3. To summarise the unit after it has been taught
  4. To provide a conceptual framework that links new content to existing knowledge Correct answer.

Explanation

An advance organiser is presented before instruction to supply a bridging framework that connects new material with what learners already know. It is a preparatory structuring device, not a test, a summary or a substitute for assessment.

Question 15Subject Knowledge (concerned teaching subject)

A mathematics teacher gives a problem that can be solved by several methods and asks students to compare the efficiency of each. Which cognitive demand does this task represent?

  1. Conceptual understanding and strategic reasoning Correct answer.
  2. Rote memorisation of a formula
  3. Procedural fluency only
  4. Speeded recall of multiplication facts

Explanation

Comparing multiple solution methods requires learners to understand underlying concepts and reason strategically about efficiency. It goes beyond executing one procedure fluently or recalling facts quickly.

Question 16Subject Knowledge (concerned teaching subject)

In a biology practical, learners measure the rate of enzyme activity at different temperatures. Which variable must be kept constant to make the comparison valid?

  1. The temperature of the water bath
  2. The concentration of the enzyme solution Correct answer.
  3. The time at which readings are taken
  4. The rate of product formation

Explanation

A fair test changes only the independent variable, temperature, while controlling all others that could affect the rate. Enzyme concentration must therefore be held constant, along with pH and substrate concentration.

Question 17Subject Knowledge (concerned teaching subject)

A teacher wants to reduce the split-attention effect when presenting a diagram with explanatory text. Which presentation choice is most consistent with this goal?

  1. Integrating labels and explanatory text directly into the diagram Correct answer.
  2. Reading the text aloud while students look only at the diagram
  3. Removing all labels and asking students to guess their meaning
  4. Placing the text in a separate appendix at the back of the book

Explanation

The split-attention effect occurs when learners must mentally integrate separated sources of information, increasing cognitive load. Physically integrating text and labels with the diagram reduces that unnecessary search and integration effort.

Question 18Subject Knowledge (concerned teaching subject)

In a physics lesson on electric circuits, a student claims that current is used up as it passes through a bulb. Which response best addresses the misconception?

  1. Current is the same at all points in a series circuit; energy is transferred, not current consumed Correct answer.
  2. Current decreases after each component because electrons are absorbed
  3. Current increases after the bulb because the filament accelerates electrons
  4. Current is used up only in parallel circuits, not series circuits

Explanation

In a series circuit charge is conserved, so the current is identical at every point. The bulb transfers electrical energy to light and heat, but the charge carriers are not consumed, which is the key distinction the misconception misses.

Question 19Subject Knowledge (concerned teaching subject)

A teacher wants to give effective feedback on a written assignment. Which feedback approach best supports improvement?

  1. A single grade with no comments
  2. Comments that identify specific strengths and concrete next steps Correct answer.
  3. Correcting every error in red without explanation
  4. Praise such as 'good effort' without reference to criteria

Explanation

Effective feedback is specific, criterion-referenced and actionable, telling learners what was done well and what to do next. Grades alone, vague praise and unexplained corrections give little guidance for improvement.

Question 20Subject Knowledge (concerned teaching subject)

In a Hindi grammar lesson, a teacher explains the difference between direct and indirect speech. Which transformation correctly converts the direct sentence 'मैं कल आऊँगा' (said by Ram) into indirect speech?

  1. राम ने कहा कि मैं कल आऊँगा
  2. राम ने कहा कि वह कल आएगा Correct answer.
  3. राम ने कहा कि वह आज आएगा
  4. राम ने कहा कि वह कल आया

Explanation

In indirect speech the first-person pronoun changes to third person and the future tense is shifted appropriately, giving 'वह कल आएगा'. The reporting verb 'कहा' introduces the clause with 'कि', and the original speaker's 'मैं' cannot be retained.

Question 21Subject Knowledge (concerned teaching subject)

A teacher wants to promote conceptual change when learners hold a misconception. Which approach is most consistent with research on conceptual change?

  1. Avoiding any discussion of the incorrect idea
  2. Ignoring the misconception and presenting the correct idea repeatedly
  3. Punishing learners for giving incorrect answers
  4. Eliciting the misconception, creating cognitive conflict, then offering a plausible alternative Correct answer.

Explanation

Conceptual change is supported when learners' existing ideas are made explicit, shown to be inadequate through discrepant evidence, and replaced by an alternative that is intelligible, plausible and fruitful. Simply repeating the correct idea rarely displaces a robust misconception.

Question 22Subject Knowledge (concerned teaching subject)

A social science teacher asks students to evaluate a primary source describing a colonial census. Which question most directly addresses the source's reliability?

  1. Who commissioned the census and what categories did they choose to record? Correct answer.
  2. In which year was the document printed?
  3. What font was used in the original document?
  4. How many pages long is the census document?

Explanation

Reliability depends on provenance, purpose and the categories imposed by those who produced a source. Asking who commissioned the census and which categories were used exposes the interests and assumptions shaping the data.

Question 23Subject Knowledge (concerned teaching subject)

A teacher uses a rubric with four performance levels. Which feature makes the rubric most useful for learning?

  1. Levels labelled only as A, B, C and D without description
  2. Criteria known only to the teacher
  3. Descriptors that name observable qualities of performance at each level Correct answer.
  4. A single holistic score with no criteria

Explanation

A rubric supports learning when each level is described in observable, criterion-referenced terms that learners can use to judge and improve their work. Undescribed labels, holistic scores and hidden criteria provide no guidance.

Question 24Subject Knowledge (concerned teaching subject)

A chemistry teacher wants learners to understand the difference between ionic and covalent bonding. Which pair of examples best illustrates the contrast?

  1. NaCl and KCl as two ionic compounds
  2. O2 and N2 as two covalent compounds
  3. CO2 and H2O as two covalent compounds
  4. NaCl as an ionic compound and CO2 as a covalent compound Correct answer.

Explanation

Ionic bonding involves electron transfer between a metal and a non-metal, as in NaCl, while covalent bonding involves electron sharing between non-metals, as in CO2. A contrasting pair drawn from each category best illustrates the distinction.

Question 25Subject Knowledge (concerned teaching subject)

A teacher introduces a new topic by asking learners to predict outcomes before any instruction. What is the main pedagogical value of this prediction task?

  1. It grades prior knowledge for reporting purposes
  2. It guarantees that learners will remember the correct answer
  3. It activates prior knowledge and creates curiosity that instruction can resolve Correct answer.
  4. It replaces the need for teacher explanation

Explanation

Prediction tasks surface existing ideas and generate curiosity about whether those ideas hold, priming learners to attend to the subsequent explanation. They are formative and motivational rather than graded or a substitute for teaching.

Question 26Subject Knowledge (concerned teaching subject)

A physics teacher explains that the SI unit of electric current is the ampere. Which statement correctly defines one ampere in terms of base SI quantities?

  1. One volt of potential difference across one ohm
  2. One joule of energy transferred per second
  3. One coulomb of charge passing a cross-section per second Correct answer.
  4. One watt of power dissipated per coulomb of charge

Explanation

Current is the rate of flow of charge, so one ampere equals one coulomb per second (I = Q/t). The joule per second is the watt, and the volt-ohm relation defines the volt through Ohm's law rather than the ampere.

Question 27Subject Knowledge (concerned teaching subject)

In a chemistry lesson on periodicity, students compare the first ionisation enthalpy of sodium with that of magnesium. Which explanation best accounts for the higher value for magnesium?

  1. Magnesium has a larger atomic radius, so its outer electron is held more weakly
  2. Magnesium has one more proton and its outer electron is in the same shell, so it is held more tightly Correct answer.
  3. The outer electron in magnesium is removed from a more stable 3s orbital
  4. Magnesium has a greater effective nuclear charge acting on the same 3s subshell

Explanation

Across a period, nuclear charge increases while the outer electrons remain in the same shell, so effective nuclear attraction rises and ionisation enthalpy generally increases. The extra proton in magnesium holds the 3s electron more tightly than in sodium.

Question 28Subject Knowledge (concerned teaching subject)

A biology teacher discusses the transport of water in plants. Which statement correctly describes the role of the Casparian strip in the root?

  1. It actively pumps mineral ions from the cortex into the endodermis
  2. It stores starch that is later mobilised during germination
  3. It forces water and dissolved ions to enter the symplast pathway before reaching the xylem Correct answer.
  4. It increases the rate of transpiration by widening the apoplastic route

Explanation

The Casparian strip is a waxy band of suberin in the endodermal cell walls that blocks the apoplastic pathway. Water and ions must therefore cross a membrane and travel through the symplast before entering the xylem, allowing selective uptake.

Question 29Subject Knowledge (concerned teaching subject)

In a mathematics class, a teacher asks students to find the sum of the first n terms of an arithmetic progression whose first term is a and common difference is d. Which expression is correct?

  1. a + (n − 1)d
  2. n/2 [a + (n − 1)d]
  3. n [2a + nd]
  4. n/2 [2a + (n − 1)d] Correct answer.

Explanation

The sum of an arithmetic progression is the number of terms times the average of the first and last terms, giving Sₙ = n/2[2a + (n − 1)d]. The last term is a + (n − 1)d, which is the nth term, not the sum.

Question 30Subject Knowledge (concerned teaching subject)

A history teacher asks students to assess the reliability of a memoir written decades after the events it describes. Which consideration is most relevant to this judgement?

  1. Whether the memoir was printed by a well-known publisher
  2. The time gap between the events and the writing, and the author's purpose in writing Correct answer.
  3. Whether the author uses formal or informal language
  4. The length of the memoir compared with other accounts

Explanation

Reliability of a retrospective source depends on how much time has elapsed, which affects memory, and on the author's motives and intended audience. These factors shape selection and interpretation of events.

Question 31Subject Knowledge (concerned teaching subject)

A geography teacher explains the formation of a meander. Which process best accounts for erosion on the outer bank of a river bend?

  1. Highest velocity and therefore greatest erosive power on the outer bank Correct answer.
  2. Lateral shifting of the thalweg towards the inner bank
  3. Deposition of coarse sediment where velocity is lowest
  4. Reduced discharge on the outside of the curve

Explanation

In a bend, centrifugal force pushes the fastest flow (the thalweg) towards the outer bank, where velocity and erosion are greatest, forming a river cliff. Deposition occurs on the inner bank where flow is slower, producing a slip-off slope.

Question 32Subject Knowledge (concerned teaching subject)

In a Hindi grammar lesson, a teacher explains the use of the postposition 'ने' with transitive verbs in the perfective aspect. Which sentence correctly illustrates this construction?

  1. राम खाना खाता है।
  2. राम स्कूल गया।
  3. राम ने खाना खाया। Correct answer.
  4. राम को खाना पसंद है।

Explanation

With a transitive verb in the perfective aspect, the agent takes 'ने' and the verb agrees with the object rather than the subject. 'राम ने खाना खाया' shows the ergative pattern correctly.

Question 33Subject Knowledge (concerned teaching subject)

A teacher of English literature asks students to identify the metre of a line in which five unstressed-stressed pairs occur. Which term correctly names this metre?

  1. Iambic pentameter Correct answer.
  2. Dactylic hexameter
  3. Trochaic tetrameter
  4. Anapaestic trimeter

Explanation

An iamb is an unstressed syllable followed by a stressed one, and pentameter means five feet per line. Five iambic feet therefore give iambic pentameter.

Question 34Subject Knowledge (concerned teaching subject)

A physics teacher sets a problem in which a block slides down a frictionless incline of angle θ. Which expression gives the acceleration of the block along the incline?

  1. g tan θ
  2. g sin θ Correct answer.
  3. g cos θ
  4. g

Explanation

The component of gravitational force along the incline is mg sin θ, and dividing by mass gives acceleration g sin θ. The normal reaction balances mg cos θ, which does not contribute to motion along the plane.

Question 35Subject Knowledge (concerned teaching subject)

In a chemistry practical, a student titrates a weak acid with a strong base. Which indicator is most suitable for detecting the equivalence point?

  1. Universal indicator, which shows a continuous colour scale
  2. Phenolphthalein, which changes over pH 8.3–10.0 Correct answer.
  3. Methyl orange, which changes over pH 3.1–4.4
  4. Litmus, which changes over pH 5.0–8.0

Explanation

The salt of a weak acid and strong base hydrolyses to give an alkaline solution at equivalence, typically around pH 8–9. Phenolphthalein changes in this range and is therefore the appropriate indicator.

Question 36Subject Knowledge (concerned teaching subject)

A biology teacher explains that DNA replication is described as semi-conservative. Which observation from the Meselson–Stahl experiment supports this?

  1. After two generations, only hybrid DNA was present
  2. After one generation, DNA formed two distinct bands, one light and one heavy
  3. After one generation in ¹⁵N medium, all DNA was of intermediate density Correct answer.
  4. After one generation, DNA formed a single heavy band

Explanation

In the Meselson–Stahl experiment, DNA grown for one generation in ¹⁵N produced a single band of intermediate density, consistent with each molecule containing one old and one new strand. This is the signature of semi-conservative replication.

Question 37Subject Knowledge (concerned teaching subject)

A mathematics teacher asks students to determine the derivative of sin(x²) with respect to x. Which result is correct?

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

Explanation

Applying the chain rule, the derivative of sin(u) is cos(u) multiplied by du/dx. With u = x², du/dx = 2x, giving 2x cos(x²).

Question 38Subject Knowledge (concerned teaching subject)

A geography teacher discusses the Indian monsoon. Which factor is most directly responsible for the reversal of wind direction between summer and winter?

  1. The presence of the Himalayas blocking all airflow
  2. Coriolis force acting alone on the trade winds
  3. Permanent high pressure over the Bay of Bengal
  4. Differential heating of land and sea producing a pressure gradient Correct answer.

Explanation

The monsoon is essentially a large-scale seasonal reversal driven by differential heating: land heats faster in summer, creating low pressure that draws moist air from the sea, while the pattern reverses in winter.

Question 39Subject Knowledge (concerned teaching subject)

In a physics lesson on optics, a student claims that a convex lens always forms a real image. Which counter-example correctly refutes this?

  1. An object placed at the centre of curvature
  2. An object placed between the lens and its focal point Correct answer.
  3. An object placed beyond twice the focal length
  4. An object placed at twice the focal length

Explanation

When an object lies within the focal length of a converging lens, the rays diverge after refraction and a virtual, erect, magnified image is formed. This is the principle of a magnifying glass.

Question 40Subject Knowledge (concerned teaching subject)

A chemistry teacher explains hybridisation in carbon compounds. Which statement correctly describes the bonding in ethyne (C₂H₂)?

  1. Each carbon is sp³ hybridised and forms four sigma bonds
  2. Each carbon is sp hybridised and forms two sigma bonds to the other carbon
  3. Each carbon is sp hybridised and forms one sigma and two pi bonds to the other carbon Correct answer.
  4. Each carbon is sp² hybridised and forms a double bond to the other carbon

Explanation

In ethyne each carbon uses two sp hybrid orbitals: one for the C–C sigma bond and one for the C–H sigma bond. The remaining two unhybridised p orbitals on each carbon overlap sideways to form two pi bonds, giving the triple bond.

Question 41Subject Knowledge (concerned teaching subject)

A teacher of political science discusses the Indian Constitution. Which feature reflects the principle of federalism with a strong central tendency?

  1. The provision for a single, integrated judiciary
  2. The division of powers between the Union and States in the Seventh Schedule Correct answer.
  3. The procedure for constitutional amendment under Article 368
  4. The existence of a written constitution

Explanation

The Seventh Schedule divides subjects into the Union, State and Concurrent Lists, with residuary powers resting with the Union. This division, together with provisions such as emergency powers, expresses federalism with a strong centralising tendency.

Question 42Subject Knowledge (concerned teaching subject)

In a mathematics class on probability, two events A and B satisfy P(A) = 0.4, P(B) = 0.5 and P(A ∩ B) = 0.2. Which statement is correct?

  1. A and B are neither independent nor mutually exclusive
  2. A and B are mutually exclusive
  3. A and B are dependent with P(A|B) = 0.4
  4. A and B are independent but not mutually exclusive Correct answer.

Explanation

Events are independent when P(A ∩ B) = P(A)P(B). Here 0.4 × 0.5 = 0.2, which equals the given intersection, so the events are independent. Since the intersection is not zero, they are not mutually exclusive.

Question 43Subject Knowledge (concerned teaching subject)

A biology teacher asks learners to distinguish between mitosis and meiosis. Which feature is unique to meiosis?

  1. Formation of a spindle apparatus
  2. Chromosome replication before division
  3. Pairing of homologous chromosomes and crossing over Correct answer.
  4. Cytokinesis following nuclear division

Explanation

Homologous chromosomes pair during prophase I of meiosis and exchange segments by crossing over, generating genetic variation. This pairing is absent in mitosis.

Question 44Subject Knowledge (concerned teaching subject)

A physics teacher explains the photoelectric effect. Which observation cannot be explained by the classical wave model of light?

  1. Emission occurs only above a threshold frequency, regardless of intensity Correct answer.
  2. Brighter light illuminates a metal surface more strongly
  3. The number of emitted electrons increases with intensity
  4. Light of higher intensity produces more electrons

Explanation

The wave model predicts that sufficient intensity should eventually supply the energy for emission at any frequency. The observed threshold frequency, below which no electrons are emitted however intense the light, requires the photon concept.

Question 45Subject Knowledge (concerned teaching subject)

In a Hindi literature lesson, a teacher introduces the poet Kabir. Which statement correctly characterises his work?

  1. He composed only in Persian for royal patrons
  2. He wrote exclusively in Braj about Krishna's childhood
  3. He composed devotional verses in the nirguna tradition using simple, colloquial language Correct answer.
  4. He wrote courtly epics in highly ornamented Sanskrit

Explanation

Kabir's verses belong to the nirguna bhakti tradition, emphasising a formless divine and using everyday language accessible to ordinary people. His dohas are direct and often critical of ritual and orthodoxy.

Question 46Subject Knowledge (concerned teaching subject)

A mathematics teacher asks students to find the value of the definite integral of x² from 0 to 3. Which value is correct?

  1. 27
  2. 9 Correct answer.
  3. 6
  4. 3

Explanation

The antiderivative of x² is x³/3. Evaluating from 0 to 3 gives 27/3 − 0 = 9.

Question 47Subject Knowledge (concerned teaching subject)

A chemistry teacher demonstrates that ammonia acts as a Lewis base. Which statement correctly explains this behaviour?

  1. It releases hydroxide ions without reacting with water
  2. It donates its lone pair of electrons to form a coordinate bond Correct answer.
  3. It donates a proton to water
  4. It accepts an electron pair from a proton

Explanation

A Lewis base is an electron-pair donor. Ammonia's nitrogen atom has a lone pair that it donates to an electron-deficient species such as a proton or BF₃, forming a coordinate bond.

Question 48Subject Knowledge (concerned teaching subject)

A geography teacher asks students to interpret a population pyramid with a broad base and narrow apex. Which conclusion is best supported?

  1. A population with balanced age distribution
  2. A young population with high birth rates and lower life expectancy Correct answer.
  3. A high proportion of elderly dependents
  4. A declining population with low birth rates

Explanation

A broad base indicates a large number of children, reflecting high birth rates, while the narrow apex indicates relatively few elderly people, consistent with lower life expectancy. This is typical of many developing economies.

Question 49Subject Knowledge (concerned teaching subject)

A teacher of English grammar explains the use of the passive voice. Which transformation of 'The committee approved the proposal' is grammatically correct?

  1. The proposal was approved by the committee Correct answer.
  2. The proposal is approved by the committee
  3. The proposal has approved by the committee
  4. The proposal was approving by the committee

Explanation

The simple past active 'approved' becomes 'was approved' in the passive, with the object promoted to subject and the agent introduced by 'by'. This preserves the original tense.

Question 50Subject Knowledge (concerned teaching subject)

In a physics lesson on thermodynamics, a gas is compressed adiabatically. Which statement correctly describes the process?

  1. No heat is exchanged, so work done on the gas raises its internal energy Correct answer.
  2. Heat flows out of the gas to keep temperature constant
  3. Internal energy remains constant while pressure rises
  4. Temperature falls because the gas does work on the surroundings

Explanation

In an adiabatic process Q = 0, so by the first law the work done on the gas increases its internal energy. For an ideal gas, this raises the temperature.