JEE Main 2021 · March session
JEE Main 18 March 2021, Shift 2
90 questions: 30 numerical-answer and 60 multiple choice. 8 were rated hard and 31 easy. Its hard-question count was the joint 12th highest of the 24 2021 shifts Lumi analysed. The biggest chapter was Amines, with 3 questions.
- Questions
- 90
- none dropped
- Numerical answer
- 30
- 33% of the shift
- Hard
- 8
- 9% of the shift
- Chapters asked
- 68
- 14 questions with a figure
Key findings · 18 Mar 2021, Shift 2
- 1
8 hard questions (9%): the joint 12th highest count of the 24 2021 shifts Lumi analysed. Across those shifts the hard share ran from 3% to 17%.
- 2
Maths was the hardest section, with 7 of 30 rated hard; Physics had the most easy questions (14 of 30).
- 3
45 questions tested a new idea, one no earlier year had asked: 63% of the 72 questions tagged to an idea.
- 4
24 came back from 2020: the same idea had been asked in the 2020 shifts Lumi analysed.
- 5
44 shared an idea with another 2021 shift (61% of tagged questions). Shifts in the same year can test the same idea in a new setting.
- 6
Biggest chapters: Gravitation in Physics (3), Amines in Chemistry (3) and Application of Derivatives in Maths (2).
The shift at a glance
Subjects, difficulty and chapters
Top chapters
Top chapters
Top chapters
- Single correct45 Q
- Numerical value30 Q
- Diagram based7 Q
- Two statements3 Q
- Match the list3 Q
- Other2 Q
- Multi-step25 Q
- Calculation22 Q
- Conceptual17 Q
- Application12 Q
- Recall9 Q
- Data or graph3 Q
- Diagram reading2 Q
Most common: Multi-step.
Against the other 2021 shifts
This shift next to the 23 other 2021 shifts Lumi analysed
Shares are of each shift’s scored questions. The highlighted row is this shift.
| Shift | Questions | Easy | Hard | Numerical | New ideas | Multi-step |
|---|---|---|---|---|---|---|
| 24 Feb, Shift 1 | 90 | 36% | 7% | 33% | 68% | 24% |
| 24 Feb, Shift 2 | 88 | 43% | 5% | 32% | 63% | 21% |
| 25 Feb, Shift 1 | 90 | 23% | 11% | 33% | 65% | 30% |
| 25 Feb, Shift 2 | 89 | 35% | 10% | 34% | 67% | 24% |
| 26 Feb, Shift 1 | 88 | 50% | 3% | 33% | 78% | 17% |
| 26 Feb, Shift 2 | 90 | 27% | 12% | 33% | 80% | 29% |
| 16 Mar, Shift 2 | 90 | 31% | 7% | 33% | 69% | 33% |
| 17 Mar, Shift 1 | 89 | 39% | 8% | 34% | 61% | 26% |
| 17 Mar, Shift 2 | 89 | 36% | 17% | 34% | 66% | 32% |
| 18 Mar, Shift 1 | 90 | 40% | 9% | 33% | 74% | 24% |
| 18 Mar, Shift 2 | 90 | 34% | 9% | 33% | 63% | 28% |
| 22 Jul, Shift 2 | 90 | 40% | 12% | 33% | 67% | 28% |
| 25 Jul, Shift 1 | 90 | 31% | 13% | 33% | 56% | 34% |
| 25 Jul, Shift 2 | 90 | 48% | 3% | 33% | 63% | 27% |
| 3 Aug, Shift 1 | 90 | 32% | 11% | 33% | 68% | 21% |
| 3 Aug, Shift 2 | 90 | 32% | 7% | 33% | 61% | 24% |
| 4 Aug, Shift 1 | 90 | 40% | 8% | 33% | 62% | 29% |
| 4 Aug, Shift 2 | 90 | 32% | 7% | 33% | 65% | 41% |
| 26 Aug, Shift 1 | 89 | 27% | 15% | 34% | 66% | 30% |
| 26 Aug, Shift 2 | 89 | 21% | 9% | 34% | 60% | 28% |
| 27 Aug, Shift 1 | 90 | 27% | 13% | 33% | 63% | 34% |
| 27 Aug, Shift 2 | 90 | 29% | 9% | 33% | 72% | 29% |
| 31 Aug, Shift 1 | 90 | 27% | 11% | 33% | 70% | 24% |
| 31 Aug, Shift 2 | 90 | 30% | 13% | 33% | 72% | 31% |
New ideas: share of a shift’s questions testing an idea no earlier year had asked. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.
Drill down
What this shift asked, and its history
Every chapter this shift asked, with all its topics and ideas. Counts and squares cover every analysed shift from 2017 to 2026; rows this shift did not ask are faded, and each row lists this shift’s questions with the most recent from other shifts.
Squares are the 8 years with analysed shifts, 2017 to 2026. A number is the questions that year when there is more than one; the shade is scaled to one shift, so a year with more analysed shifts (1 to 24 a year) does not look darker. Share is of the level above.
Every question
All 90 questions of this shift
The opening words of each question, with its chapter, topic, idea and how hard it was. Open one for the full text, options and the official answer. “New idea” means no earlier year had tested it.
Physics30 questions
14 easy15 medium1 hard
- Q1Consider a sample of oxygen behaving like an ideal gas. At 300 K, the ratio of root mean square (rms) velocity to the average velocity of gas molecule would be : (Molecular weight of oxygen is 32 g/mol; R J K mol)
Kinetic TheoryKinetic Theory of GasesMolecular Speed Ratios
EasySingle correctNew ideaIdea asked in 4 years
- Q2
- Q3A particle of mass m moves in a circular orbit under the central potential field, , where C is a positive constant. The correct radius –velocity graph of the particle’s motion is :
GravitationOrbital MechanicsOrbital Velocity
MediumDiagram based · figureIdea asked in 5 yearsAsked the year before
- Q4A solid cylinder of mass m is wrapped with an inextensible light string and, is placed on a rough inclined plane as shown in the figure. The frictional force acting between the cylinder and the inclined plane is : [The coefficient of static friction,…
System of Particles and Rotational MotionFrictionDirection of Static Friction
HardDiagram based · figureNew idea
- Q5If the angular velocity of earth’s spin is increased such that the bodies at the equator start floating, the duration of the day would be approximately : [Take g ms, the radius of earth, R m, Take ]
GravitationOrbital MechanicsOrbital Time Period
MediumSingle correctIdea asked in 6 yearsAsked the year before
- Q6Consider a uniform wire of mass M and length L. It is bent into a semicircle. Its moment of inertia about a line perpendicular to the plane of the wire passing through the centre is :
System of Particles and Rotational MotionMoment of InertiaMOI Change by Bending a Rod
EasySingle correctNew ideaIdea asked in 2 years
- Q7The speed of electrons in a scanning electron microscope is ms. If the protons having the same speed are used instead of electrons, then the resolving power of scanning proton microscope will be changed by a factor of :
Dual Nature of Radiation and MatterMatter WavesWavelength Ratios of Different Particles
MediumSingle correctIdea asked in 6 yearsAsked the year before
- Q8
- Q9For an adiabatic expansion of an ideal gas, the fractional change in its pressure is equal to (where is the ratio of specific heats) :
ThermodynamicsThermodynamic ProcessesAdiabatic Process Analysis
EasySingle correctIdea asked in 7 yearsAsked the year before
- Q10
- Q11An ideal gas in a cylinder is separated by a piston in such a way that the entropy of one part is and that of the other part is . Given that . If the piston is removed then the total entropy of the system will be :
ThermodynamicsSecond Law and EntropyExtensive Nature of Entropy
EasySingle correctNew idea
- Q12The function of time representing a simple harmonic motion with a period of is :
OscillationsSHM EquationsSHM Definition and Force Law
MediumSingle correctNew ideaIdea asked in 4 years
- Q13In a series LCR circuit, the inductive reactance () is 10 and the capacitive reactance () is 4 . The resistance (R) in the circuit is 6 . The power factor of the circuit is :
Alternating CurrentPhasor DiagramsPower Factor from Phasors
EasySingle correctIdea asked in 5 yearsAsked the year before
- Q14Which of the following statements are correct ? (A) Electric monopoles do not exist whereas magnetic monopoles exist. (B) Magnetic field lines due to a solenoid at its ends and outside cannot be completely straight and confined. (C) Magnetic field lines are…
Magnetism and MatterAmpere's Circuital LawToroidal Magnetic Field
MediumOtherNew idea
- Q15
- Q16A proton and an -particle, having kinetic energies and respectively, enter into a magnetic field at right angles. The ratio of the radii of trajectory of proton to that of -particle is 2 : 1. The ratio of is :
Moving Charges and MagnetismLorentz ForceCircular Motion in Uniform B-Field
MediumSingle correctIdea asked in 4 yearsAsked the year before
- Q17Three rays of light, namely red (R), green (G) and blue (B) are incident on the face PQ of a right angled prism PQR as shown in the figure. The refractive indices of the material of the prism for red, green and blue wavelength are 1.27, 1.42 and 1.49…
Ray Optics and Optical InstrumentsRefraction and Snell's LawWavelength Dependence of TIR
MediumDiagram based · figureNew idea
- Q18
- Q19
- Q20The decay of a proton to neutron is :
NucleiRadioactive DecayBeta Decay Mechanisms
MediumSingle correctNew idea
- Q21The projectile motion of a particle of mass 5 g is shown in the figure. The initial velocity of the particle is ms and the air resistance is assumed to be negligible. The magnitude of the change in momentum between the points A and B is…
Motion in a PlaneProjectile MotionChange in Momentum During Flight
EasyNumerical value · figureNew idea
- Q22An infinite number of point charges, each carrying 1 C charge, are placed along the -axis at m, 2 m, 4 m, 8 m ................. . The total force on a 1 C point charge, placed at the origin, is N. The value of , to the nearest…
Electric Charges and FieldsCoulomb's LawSuperposition of Forces
MediumNumerical valueNew ideaIdea asked in 3 years
- Q23Two wires of same length and thickness having specific resistances 6 cm and 3 cm respectively are connected in parallel. The effective resistivity is cm. The value of , to the nearest integer, is _________.
Current ElectricityOhm's Law and ResistanceResistivity and Geometry
EasyNumerical valueIdea asked in 4 yearsAsked the year before
- Q24A ball of mass 4 kg, moving with a velocity of 10 ms, collides with a spring of length 8 m and force constant 100 Nm. The length of the compressed spring is m. The value of , to the nearest integer, is _________.
Work, Energy and PowerWork and Kinetic EnergyMaximum Compression of a Spring
EasyNumerical valueNew ideaIdea asked in 3 years
- Q25The typical output characteristics curve for a transistor working in the common-emitter configuration is shown in the figure. The estimated current gain from the figure is _________.
Semiconductor Electronics: Materials, Devices and Simple CircuitsTransistorsCE Configuration Characteristics
MediumNumerical value · figureNew idea
- Q26Consider a 72 cm long wire AB as shown in the figure. The galvanometer jockey is placed at P on AB at a distance cm from A. The galvanometer shows zero deflection. The value of , to the nearest integer, is _________.
Current ElectricityWheatstone BridgeMeter Bridge Principles
EasyNumerical value · figureIdea asked in 4 yearsAsked the year before
- Q27A galaxy is moving away from the earth at a speed of 286 kms. The shift in the wavelength of a redline at 630 nm is m. The value of , to the nearest integer, is _________. [Take the value of speed of light c, as …
WavesDoppler EffectLight Doppler Approximation
EasyNumerical valueNew ideaIdea asked in 2 years
- Q28Consider a water tank as shown in the figure. It’s cross-sectional area is 0.4 m. The tank has an opening B near the bottom whose cross-section area is 1 cm. A load of 24 kg is applied on the water at the top when the height of the water level is 40…
Mechanical Properties of FluidsFluid DynamicsTorricelli's Law of Efflux
MediumNumerical value · figureNew ideaIdea asked in 2 years
- Q29
- Q30
Chemistry30 questions
14 easy16 medium0 hard
- Q31
- Q32Given below are two statements : Statement I : Bohr’s theory accounts for the stability and line spectrum of ion. Statement II : Bohr’s theory was unable to explain the splitting of spectral lines in the presence of a magnetic field. In the…
Structure of AtomBohr's Atomic TheoryLimitations of Bohr's Model
EasyTwo statementsNew idea
- Q33
- Q34The first ionization energy of magnesium is smaller as compared to that of elements X and Y, but higher than that of Z. The elements X, Y and Z, respectively, are :
Classification of Elements and Periodicity in PropertiesPeriodic TrendsIonization Enthalpy Trends
EasySingle correctIdea asked in 6 yearsAsked the year before
- Q35Match List - I with List - II : List - I List - II (a) Mercury (i) Vapour phase refining (b) Copper (ii) Distillation Refining (c) Silicon (iii) Electrolytic Refining (d) Nickel (iv) Zone Refining Choose the most appropriate answer from the option given…
General Principles and Processes of Isolation of ElementsMetallurgical ExtractionMetal Refining Techniques
EasyMatch the listIdea asked in 4 yearsAsked the year before
- Q36
- Q37
- Q38The oxidation states of nitrogen in NO, , and are in the order of :
Redox ReactionsOxidation Number Assignment
EasySingle correctNew ideaIdea asked in 4 years
- Q39The oxide that shows magnetic property is :
The d- and f-Block Elementsd-Block ElementsSpin-only Magnetism
MediumSingle correctIdea asked in 6 yearsAsked the year before
- Q40
- Q41Given below are two statements : Statement I : Non-biodegradable wastes are generated by the thermal power plants. Statement II : Bio-degradable detergents leads to eutrophication. In the light of the above statements, choose the most appropriate answer from…
Environmental ChemistryEutrophication and Dissolved Oxygen Limits
EasyTwo statementsIdea asked in 3 yearsAsked the year before
- Q42Given below are two statements : Statement I : and AgCN both can generate nucleophile. Statement II : KCN and AgCN both will generate nitrile nucleophile with all reaction conditions. Choose the most appropriate option :
Haloalkanes and HaloarenesSN1 and SN2 MechanismsAmbident Nucleophiles (Cyanide/Nitrite)
MediumTwo statementsNew ideaIdea asked in 3 years
- Q43
- Q44Main Products formed during a reaction of 1-methoxy naphthalene with hydroiodic acid are :
Alcohols, Phenols and EthersEthersCleavage of Alkyl-Aryl Ethers
EasySingle correct · figureNew ideaIdea asked in 3 years
- Q45In the reaction of hypobromite with amide, the carbonyl carbon is lost as :
AminesHofmann Bromamide Degradation
EasySingle correctNew ideaIdea asked in 5 years
- Q46[figure: reaction scheme] Consider the above reaction, the product ‘X’ and ‘Y’ respectively are :
Aldehydes, Ketones and Carboxylic AcidsAldol and CannizzaroSelf-Aldol Condensation
MediumDiagram based · figureNew ideaIdea asked in 3 years
- Q47An organic compound “A” on treatment with benzene sulphonyl chloride gives compound B. B is soluble in dil. NaOH solution. Compound A is :
MediumSingle correctIdea asked in 5 yearsAsked the year before
- Q48[figure: reaction scheme] Consider the given reaction, percentage yield of :
AminesAromatic HydrocarbonsOrtho-Para vs Meta Directing
MediumDiagram based · figureNew ideaIdea asked in 5 years
- Q49Match List - I with List - II : List - I (Class of Chemicals) List - II (Example) (a) Antifertility drug (i) Meprobamate (b) Antibiotic (ii) Alitame (c) Tranquilizer (iii) Norethindrone (d) Artificial Sweetener (iv) Salvarsan Choose the most appropriate…
Chemistry in Everyday LifeDrug Classification
MediumMatch the listNew ideaIdea asked in 2 years
- Q50
- Q5110.0 mL of solution is titrated against 0.2 M HCl solution. The following titre values were obtained in 5 readings : 4.8 mL, 4.9 mL, 5.0 mL, 5.0 mL and 5.0 mL. Based on these readings, and convention of titrimetric estimation the…
Some Basic Concepts of ChemistryMole ConceptMolarity Calculation
EasyNumerical valueIdea asked in 5 yearsAsked the year before
- Q52The number of species below that have two lone pairs of electrons in their central atom is __________. (Round off to the Nearest Integer). , , , , , ,…
Chemical Bonding and Molecular StructureVSEPR TheoryTrigonal Bipyramidal Positions
MediumNumerical valueIdea asked in 5 yearsAsked the year before
- Q53
- Q54A solute A dimerizes in water. The boiling point of a 2 molal solution of A is 100.52℃. The percentage association of A is __________. (Round off to the Nearest Integer). [Use : for water = 0.52 K kg mol Boiling point of water = 100℃]
SolutionsColligative PropertiesDegree of Association from Van't Hoff Factor
MediumNumerical valueIdea asked in 3 years
- Q55
- Q56
- Q57A reaction has a half life of 1 min. The time required for 99.9% completion of the reaction is __________ min. (Round off to the Nearest Integer). [Use : ln 2 = 0.69; ln 10 = 2.3]
Chemical KineticsIntegrated Rate EquationsFirst Order Fractional Completion Shortcuts
EasyNumerical valueNew ideaIdea asked in 3 years
- Q58
- Q59[figure: reaction scheme] Consider the above reaction where 6.1 g of Benzoic acid is used to get 7.8 g of m-bromo benzoic acid. The percentage yield of the product is __________. (Round off to the Nearest Integer). [Given : Atomic masses : C : 12.0 u, H :…
Some Basic Concepts of ChemistryStoichiometryTheoretical and Percent Yield
EasyNumerical value · figureNew ideaIdea asked in 2 years
- Q60
Maths30 questions
3 easy20 medium7 hard
- Q61If , for some , then the value of is equal to :
Trigonometric FunctionsTrigonometric IdentitiesHigh Power Reduction Identities
MediumSingle correctNew ideaIdea asked in 2 years
- Q62
- Q63A pole stands vertically inside a triangular park ABC. Let the angle of elevation of the top of the pole from each corner of the park be . If the radius of the circumcircle of ABC is 2, then the height of the pole is equal to :
Trigonometric FunctionsProperties of TrianglesInradius and Circumradius
MediumSingle correctNew ideaIdea asked in 3 years
- Q64Let in a series of observations, half of them are equal to a and remaining half are equal to a. Also by adding a constant b in each of these observations, the mean and standard deviation of new set become 5 and 20, respectively. Then the value of…
StatisticsVariance and SDEffect of Linear Transformations
MediumSingle correctIdea asked in 2 yearsAsked the year before
- Q65
- Q66In a triangle ABC, if , , , then the projection of the vector on is equal to :
Vector AlgebraDot ProductScalar and Vector Projection
MediumSingle correctIdea asked in 5 yearsAsked the year before
- Q67Let the centroid of an equilateral triangle ABC be at the origin. Let one of the sides of the equilateral triangle be along the straight line . If R and r be the radius of circumcircle and incircle respectively of ABC, then is equal to :
Straight LinesStraight Line DistanceDistance from Origin to a Line
MediumSingle correctNew idea
- Q68
- Q69Let be the solution of the differential equation , , with . Then the value of at is equal to :
Differential EquationsLinear Differential EquationsBernoulli Equation Reduction
HardSingle correctNew ideaIdea asked in 2 years
- Q70
- Q71Let , where is continuous function in such that for all and for all . The largest possible interval in which lies is :
IntegralsDefinite Integral PropertiesBounding and Estimation Property
MediumSingle correctIdea asked in 3 yearsAsked the year before
- Q72Let be a function defined as If is continuous at , then the…
Continuity and DifferentiabilityFinding Unknown Constants for Continuity
MediumSingle correct · figureNew ideaIdea asked in 3 years
- Q73Let be the sum of first terms of an arithmetic progression. Let be the sum of first terms of the same arithmetic progression. If is 1000, then the sum of the first terms of the arithmetic progression is equal to :
Sequences and SeriesAP and GPAP Sum of n terms
MediumSingle correctIdea asked in 7 yearsAsked the year before
- Q74
- Q75Let the system of linear equations , . has a non-trivial solution. Then which of the following is true ?
DeterminantsCramer's RuleParameter Evaluation in Homogeneous Systems
EasySingle correctIdea asked in 5 yearsAsked the year before
- Q76Let be defined by . Let be given as . Then, the sum of all the values of for which is equal to.
Relations and FunctionsFunctions and DomainDomain and Range of Inverse Functions
MediumSingle correctNew ideaIdea asked in 2 years
- Q77
- Q78
- Q79
- Q80Let and be two non-zero vectors perpendicular to each other and . If , then the angle between the vectors…
Vector AlgebraCross ProductMagnitude and Sine Formula
MediumSingle correctIdea asked in 7 yearsAsked the year before
- Q81
- Q82Let I be an identity matrix of order and . Then the value of for which is equal to ___________.
MatricesMatrix MultiplicationCayley-Hamilton Theorem Application
MediumNumerical valueNew ideaIdea asked in 5 years
- Q83
- Q84
- Q85Let be a real polynomial of degree 3 which vanishes at . Let have local minima at , local maxima at and , then the sum of all the coefficients of the polynomial is equal to ___________.
Application of DerivativesMaxima and MinimaDetermining Coefficients from Extrema
MediumNumerical valueIdea asked in 3 yearsAsked the year before
- Q86Let be the solution of the differential equation , , with . If the area bounded by the line , , and is , then the value of is…
Differential EquationsHomogeneous EquationsSubstitution y = vx
HardNumerical valueIdea asked in 6 yearsAsked the year before
- Q87
- Q88
- Q89Let denote the binomial coefficient of in the expansion of . If , , then is equal to ___________.
Binomial TheoremBinomial CoefficientsBinomial Coefficients with AP Multiplier
MediumNumerical valueNew ideaIdea asked in 2 years
- Q90Let satisfy the equation for all and for any . If the function is differentiable at and , then …
Continuity and DifferentiabilityDifferentiability via Functional Equations
MediumNumerical valueIdea asked in 6 yearsAsked the year before
Questions from the official paper published by NTA, answers from the final key. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026; see the other 2021 shifts.