JEE Main 2024 — 5 Apr Shift 1 (Previous Year Paper)
JEE Main · 2024 · with answers and explanations
- questions
- 88
- Total marks
- 292
- Duration
- 180 minutes
- Negative marking
- −1
Subjects: Physics · Chemistry · Mathematics
Question 1
Physics · 4 marks · −1The angle between vector and the resultant of and is :
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: Resultant .
Question 2
Physics · 4 marks · −1Time periods of oscillation of the same simple pendulum measured using four different measuring clocks were recorded as 4.62 s, 4.632 s, 4.6 s and 4.64 s. The arithmetic mean of these readings in correct significant figure is :
- A.5 s
- B.4.623 s
- C.4.6 s
- D.4.62 s
Correct answer: C
Explanation: Mean 4.623 s, rounded to the least precise reading (one decimal).
Question 3
Physics · 4 marks · −1If G be the gravitational constant and u be the energy density then which of the following quantity have the dimensions as that of the :
- A.pressure gradient per unit mass
- B.Gravitational potential
- C.Energy per unit mass
- D.Force per unit mass
Correct answer: D
Explanation: , so is an acceleration.
Question 4
Physics · 4 marks · −1A wooden block of mass 5 kg rests on a soft horizontal floor. When an iron cylinder of mass 25 kg is placed on the top of the block, the floor yields and the block and the cylinder together go down with an acceleration of 0.1 m s. The action force of the system on the floor is equal to:
- A.196 N
- B.291 N
- C.294 N
- D.297 N
Correct answer: B
Explanation: N.
Question 5
Physics · 4 marks · −1A body of mass 50 kg is lifted to a height of 20 m from the ground in the two different ways as shown in the figures. The ratio of work done against the gravity in both the respective cases, will be :

- A.1 : 2
- B.
- C.2 : 1
- D.1 : 1
Correct answer: D
Question 6
Physics · 4 marks · −1Ratio of radius of gyration of a hollow sphere to that of a solid cylinder of equal mass, for moment of Inertia about their diameter axis AB as shown in figure is . The value of x is :

- A.51
- B.34
- C.17
- D.67
Correct answer: D
Explanation: Sphere: ; cylinder about a diameter of an end face: ; ratio.
Question 7
Physics · 4 marks · −1A simple pendulum doing small oscillations at a place R height above earth surface has time period of s. would be it's time period if it is brought to a point which is at a height 2R from earth surface. Choose the correct relation [R = radius of earth] :
- A.
- B.
- C.
- D.
Correct answer: D
Explanation: : .
Question 8
Physics · 4 marks · −1In hydrogen like system the ratio of coulombian force and gravitational force between an electron and a proton is in the order of :
- A.
- B.
- C.
- D.
Correct answer: A
Question 9
Physics · 4 marks · −1Match List I with List II : List I: (A) Kinetic energy of planet; (B) Gravitation Potential energy of sun-planet system; (C) Total mechanical energy of planet; (D) Escape energy at the surface of planet for unit mass object List II: (I) ; (II) ; (III) ; (IV) (Where a = radius of planet orbit, r = radius of planet, M = mass of Sun, m = mass of planet) Choose the correct answer from the options given below :
- A.(A)-(III), (B)-(IV), (C)-(I), (D)-(II)
- B.(A)-(II), (B)-(I), (C)-(IV), (D)-(III)
- C.(A)-(I), (B)-(II), (C)-(III), (D)-(IV)
- D.(A)-(I), (B)-(IV), (C)-(II), (D)-(III)
Correct answer: B
Question 10
Physics · 4 marks · −1Given below are two statements : Statement I : When a capillary tube is dipped into a liquid, the liquid neither rises nor falls in the capillary. The contact angle may be 0°. Statement II : The contact angle between a solid and a liquid is a property of the material of the solid and liquid as well. In the light of the above statement, choose the correct answer from the options given below.
- A.Both Statement I and Statement II are false
- B.Both Statement I and Statement II are true
- C.Statement I is false but Statement II is true
- D.Statement I is true and Statement II is false
Correct answer: C
Explanation: No rise or fall means a contact angle of 90°.
Question 11
Physics · 4 marks · −1The heat absorbed by a system in going through the given cyclic process is :

- A.19.6 J
- B.61.6 J
- C.616 J
- D.431.2 J
Correct answer: B
Explanation: Heat = area of the circle cc·kPa J ≈ 61.6 J.
Question 12
Physics · 4 marks · −1If the collision frequency of hydrogen molecules in a closed chamber at 27°C is Z, then the collision frequency of the same system at 127°C is :
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: At fixed number density .
Question 13
Physics · 4 marks · −1In the given figure , , and . Battery is ideal with emf 12 V. Equivalent resistant of the circuit and current supplied by battery are respectively :

- A.10.5Ω and 1.14 A
- B.12Ω and 1 A
- C.10.5Ω and 1 A
- D.12Ω and 11.4 A
Correct answer: B
Explanation: ; total 12 Ω, 1 A.
Question 14
Physics · 4 marks · −1In a co-axial straight cable, the central conductor and the outer conductor carry equal currents in opposite directions. The magnetic field is zero :
- A.outside the cable
- B.inside the outer conductor
- C.inside the inner conductor
- D.in between the two conductors
Correct answer: A
Question 15
Physics · 4 marks · −1Two conducting circular loops A and B are placed in the same plane with their centers coinciding as shown in figure. The mutual inductance between them is :

- A.
- B.
- C.
- D.
Correct answer: D
Explanation: Field of B at the centre threads area .
Question 16
Physics · 4 marks · −1An alternating voltage of amplitude 40 V and frequency 4 kHz is applied directly across the capacitor of 12 μF. The maximum displacement current between the plates of the capacitor is nearly :
- A.10 A
- B.12 A
- C.8 A
- D.13 A
Correct answer: B
Explanation: A.
Question 17
Physics · 4 marks · −1Light emerges out of a convex lens when a source of light kept at its focus. The shape of wavefront of the light is :
- A.both spherical and cylindrical
- B.plane
- C.spherical
- D.cylindrical
Correct answer: B
Question 18
Physics · 4 marks · −1Given below are two statements : Statement I : Figure shows the variation of stopping potential with frequency (ν) for the two photosensitive materials and . The slope gives value of , where h is Planck's constant, e is the charge of electron. Statement II : will emit photoelectrons of greater kinetic energy for the incident radiation having same frequency. In the light of the above statements, choose the most appropriate answer from the options given below.

- A.Both Statement I and Statement II are correct
- B.Statement I is incorrect but Statement II is correct
- C.Both Statement I and Statement II are incorrect
- D.Statement I is correct and Statement II is incorrect
Correct answer: D
Explanation: Same slope ; has the larger work function, so its electrons are less energetic.
Question 19
Physics · 4 marks · −1An electron rotates in a circle around a nucleus having positive charge Ze. Correct relation between total energy (E) of electron to its potential energy (U) is :
- A.E = U
- B.2E = U
- C.2E = 3U
- D.E = 2U
Correct answer: B
Question 20
Physics · 4 marks · −1Following gates section is connected in a complete suitable circuit. For which of the following combination, bulb will glow (ON) :

- A.A = 0, B = 0, C = 0, D = 1
- B.A = 0, B = 1, C = 1, D = 1
- C.A = 1, B = 0, C = 0, D = 0
- D.A = 1, B = 1, C = 1, D = 0
Correct answer: C
Explanation: For (3): , , NOR gives 0, while — different levels, bulb glows.
Question 21
Physics · 4 marks · −1A body moves on a frictionless plane starting from rest. If is distance moved between t = n − 1 and t = n and is distance moved between t = n − 2 and t = n − 1, then the ratio is for n = 10. The value of x is ______.
Correct answer: 19
Explanation: .
Question 22
Physics · 4 marks · −1Three blocks , , having masses 4 kg, 6 kg and 10 kg respectively are hanging from a smooth pully using rope 1, 2 and 3 as shown in figure. The tension in the rope 1, when they are moving upward with acceleration of 2 m s is ______ N (if g = 10 m/s²).

Correct answer: 240
Explanation: N.
Question 23
Physics · 4 marks · −1The density and breaking stress of a wire are kg/m³ and N/m² respectively. The wire is suspended from a rigid support on a planet where acceleration due to gravity is rd of the value on the surface of earth. The maximum length of the wire with breaking is ______ m (take, g = 10 m/s²).
Correct answer: 600
Explanation: m.
Question 24
Physics · 4 marks · −1Three capacitors of capacitances 25 μF, 30 μF and 45 μF are connected in parallel to a supply of 100 V. Energy stored in the above combination is E. When these capacitors are connected in series to the same supply, the stored energy is . The value of x is ______.
Correct answer: 86
Explanation: Series capacitance μF vs parallel 100 μF: ratio .
Question 25
Physics · 4 marks · −1The electric field between the two parallel plates of a capacitor of 1.5 μF capacitance drops to one third of its initial value in 6.6 μs when the plates are connected by a thin wire. The resistance of this wire is ______ Ω. (Given, log 3 = 1.1)
Correct answer: 4
Explanation: .
Question 26
Physics · 4 marks · −1In the experiment to determine the galvanometer resistance by half-deflection method, the plot of vs the resistance (R) of the resistance box is shown in the figure. The figure of merit of the galvanometer is ______ A/division. [The source has emf 2V]

Correct answer: 5
Explanation: : slope A/div.
Question 27
Physics · 4 marks · −1A 2 A current carrying straight metal wire of resistance 1Ω, resistivity Ωm, area of cross-section 10 mm² and mass 500 g is suspended horizontally in mid air by applying a uniform magnetic field . The magnitude of B is ______ T (given, g = 10 m/s²).
Correct answer: 5
Explanation: m; T.
Question 28
Physics · 4 marks · −1An ac source is connected in given series LCR circuit. The rms potential difference across the capacitor of 20 μF is ______ V.

Correct answer: 50
Explanation: , , ; A; V.
Question 29
Physics · 4 marks · −1In Young's double slit experiment, carried out with light of wavelength 5000 Å, the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at x = 0 cm. The value of x for third maxima is ______ mm.
Correct answer: 10
Explanation: mm.
Question 30
Physics · 4 marks · −1If three helium nuclei combine to form a carbon nucleus then the energy released in this reaction is ______ MeV. (Given 1u = 931 MeV/c², atomic mass of helium = 4.002603 u)
Correct answer: 727
Explanation: u → 7.27 MeV.
Question 31
Chemistry · 4 marks · −1An organic compound has 42.1% carbon, 6.4% hydrogen and remainder is oxygen. If its molecular weight is 342, then its molecular formula is :
- A.
- B.
- C.
- D.
Correct answer: C
Question 32
Chemistry · 4 marks · −1The incorrect postulates of the Dalton's atomic theory are : (A) Atoms of different elements differ in mass. (B) Matter consists of divisible atoms. (C) Compounds are formed when atoms of different element combine in a fixed ratio. (D) All the atoms of given element have different properties including mass. (E) Chemical reactions involve reorganisation of atoms. Choose the correct answer from the options given below :
- A.(C), (D), (E) only
- B.(B), (D) only
- C.(A), (B), (D) only
- D.(B), (D), (E) only
Correct answer: B
Question 33
Chemistry · 4 marks · −1Given below are two statements : Statement I : In group 13, the stability of +1 oxidation state increases down the group. Statement II : The atomic size of gallium is greater than that of aluminium. In the light of the above statements, choose the most appropriate answer from the options given below :
- A.Both Statement I and Statement II are correct
- B.Statement I is incorrect but Statement II is correct
- C.Both Statement I and Statement II are incorrect
- D.Statement I is correct but Statement II is incorrect
Correct answer: D
Explanation: Ga (135 pm) is smaller than Al (143 pm).
Question 34
Chemistry · 4 marks · −1The statement(s) that are correct about the species , , and . (A) All are isoelectronic (B) All have the same nuclear charge (C) has the largest ionic radii (D) has the smallest ionic radii Choose the most appropriate answer from the options given below :
- A.(B), (C) and (D) only
- B.(C) and (D) only
- C.(A), (C) and (D) only
- D.(A), (B), (C) and (D)
Correct answer: C
Question 35
Chemistry · 4 marks · −1The following reaction occurs in the Blast furnance where iron ore is reduced to iron metal . Using the Le-chatelier's principle, predict which one of the following will not disturb the equilibrium.
- A.Addition of
- B.Removal of
- C.Addition of
- D.Removal of CO
Correct answer: C
Explanation: Adding a pure solid does not change the reaction quotient.
Question 36
Chemistry · 4 marks · −1The number of neutrons present in the more abundant isotope of boron is 'x'. Amorphous boron upon heating with air forms a product, in which the oxidation state of boron is 'y'. The value of x + y is ______
- A.3
- B.9
- C.4
- D.6
Correct answer: B
Explanation: B has 6 neutrons; BO has B(+3).
Question 37
Chemistry · 4 marks · −1Number of σ and π bonds present in ethylene molecule is respectively :
- A.4 and 1
- B.5 and 2
- C.3 and 1
- D.5 and 1
Correct answer: D
Question 38
Chemistry · 4 marks · −1For the Compounds : (A) (B) (C) (D) . The increasing order of boiling point is : Choose the correct answer from the options given below :
- A.(D) < (C) < (A) < (B)
- B.(B) < (A) < (C) < (D)
- C.(A) < (B) < (C) < (D)
- D.(B) < (A) < (D) < (C)
Correct answer: B
Explanation: Alkane < ether < ketone (dipolar) < alcohol (H-bonding).
Question 39
Chemistry · 4 marks · −1Given below are two statements: Statement I : Nitration of benzene involves the following step - . Statement II : Use of Lewis base promotes the electrophilic substitution of benzene. In the light of the above statements, choose the most appropriate answer from the options given below :
- A.Statement I is correct but Statement II is incorrect
- B.Statement I is incorrect but Statement II is correct
- C.Both Statement I and Statement II are correct
- D.Both Statement I and Statement II are incorrect
Correct answer: A
Question 40
Chemistry · 4 marks · −1The reaction at cathode in the cells commonly used in clocks involves.
- A.reduction of Mn from +7 to +2
- B.reduction of Mn from +4 to +3
- C.oxidation of Mn from +3 to +4
- D.oxidation of Mn from +2 to +7
Correct answer: B
Question 41
Chemistry · 4 marks · −1Molar ionic conductivities of divalent cation and anion are 57 S cm² mol and 73 S cm² mol respectively. The molar conductivity of solution of an electrolyte with the above cation and anion will be :
- A.187 S cm² mol
- B.260 S cm² mol
- C.130 S cm² mol
- D.65 S cm² mol
Correct answer: C
Question 42
Chemistry · 4 marks · −1The metal that shows highest and maximum number of oxidation state is :
- A.Fe
- B.Mn
- C.Co
- D.Ti
Correct answer: B
Question 43
Chemistry · 4 marks · −1Which one of the following complexes will exhibit the least paramagnetic behaviour? [Atomic number, Cr = 24, Mn = 25, Fe = 26, Co = 27]
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: Unpaired electrons 4, 4, 3, 5.
Question 44
Chemistry · 4 marks · −1The correct order of ligands arranged in increasing field strength.
- A.F < Br < I < NH
- B.Br < F < HO < NH
- C.HO < OH < CN < NH
- D.Cl < OH < Br < CN
Correct answer: B
Question 45
Chemistry · 4 marks · −1Given below are two statement: Statements I : Bromination of phenol in solvent with low polarity such as or requires Lewis acid catalyst. Statements II : The Lewis acid catalyst polarises the bromine to generate Br. In the light of the above statements, choose the correct answer from the options given below :
- A.Both Statement I and Statement II are true
- B.Statement I is true but Statement II is false
- C.Statement I is false but Statement II is true
- D.Both Statement I and Statement II are false
Correct answer: C
Question 46
Chemistry · 4 marks · −1Identify compound (Z) in the following reaction sequence. Chlorobenzene + NaOH X Y Z
- A.2,4,6-Trinitrophenol (picric acid)
- B.2,4-Dinitrophenol
- C.2-Nitrophenol
- D.4-Nitrophenol
Correct answer: A
Explanation: Dow process to phenol, then nitration with concentrated nitric acid gives picric acid.
Question 47
Chemistry · 4 marks · −1Identify 'A' in the following reaction: Butan-2-one 'A'
- A.Butan-2-ol
- B.Acetone hydrazone ()
- C.Butan-2-one hydrazone
- D.n-Butane
Correct answer: D
Question 48
Chemistry · 4 marks · −1Which of the following gives a positive test with ninhydrin?
- A.Starch
- B.Egg albumin
- C.Polyvinyl chloride
- D.Cellulose
Correct answer: B
Question 49
Chemistry · 4 marks · −19.3 g of pure aniline is treated with bromine water at room temperature to give a white precipitate of the product 'P'. The mass of product 'P' obtaind is 26.4 g. The percentage yield is ______ %.
Correct answer: 80
Explanation: 0.1 mol 2,4,6-tribromoaniline = 33 g; .
Question 50
Chemistry · 4 marks · −1The value of Rydberg constant is J. The velocity of electron having mass kg in Bohr's first orbit of hydrogen atom = ______ m s (nearest integer).
Correct answer: 22
Explanation: m/s.
Question 51
Chemistry · 4 marks · −1In the lewis dot structure for , total number of valence electrons around nitrogen is ______
Correct answer: 8
Question 52
Chemistry · 4 marks · −1The heat of combustion of solid benzoic acid at constant volume is −321.30 kJ at 27°C. The heat of combustion at constant pressure is (−321.30 − x R) kJ, the value of x is ______.
Correct answer: 150
Explanation: ; (with R in the units of the problem).
Question 53
Chemistry · 4 marks · −1An artificial cell is made by encapsulating 0.2M glucose solution within a semipermeable membrane. The osmotic pressure developed when the artificial cell is placed within a 0.05M solution of NaCl at 300 K is ______ bar. (nearest integer). [Given : R = 0.083 L bar mol K] Assume complete dissociation of NaCl
Correct answer: 25
Explanation: Net concentration difference M; bar.
Question 54
Chemistry · 4 marks · −1During Kinetic study of reaction 2A + B → C + D, the following results were obtained : | | A [M] | B [M] | initial rate of formation of D | | I | 0.1 | 0.1 | | | II | 0.3 | 0.2 | | | III | 0.3 | 0.4 | | | IV | 0.4 | 0.1 | | Based on above data, overall order of the reaction is ______
Correct answer: 3
Explanation: First order in A (I→IV), second order in B (II→III).
Question 55
Chemistry · 4 marks · −1The spin-only magnetic moment value of the ion among , , and , that acts as strong oxidising agent in aqueous solution is ______ BM (Near integer). (Given atomic numbers : Ti : 22, V : 23, Cr : 24, Co : 27)
Correct answer: 5
Question 56
Chemistry · 4 marks · −1The number of halobenzenes from the following that can be prepared by Sandmeyer's reaction is ______ (I) fluorobenzene (II) chlorobenzene (III) bromobenzene (IV) iodobenzene (V) astatobenzene
Correct answer: 2
Explanation: Only chloro- and bromobenzene.
Question 57
Chemistry · 4 marks · −1Consider the given chemical reaction sequence : Phenol Product A Product B. Total sum of oxygen atoms in Product A and Product B are ______
Correct answer: 14
Explanation: A = phenol-2,4-disulphonic acid (7 O), B = picric acid (7 O).
Question 58
Chemistry · 4 marks · −1In a borax bead test under hot condition, a metal salt (one from the given) is heated at point B of the flame, resulted in green colour salt bead. The spin-only magnetic moment value of the salt is ______ BM (Nearest integer) [Given atomic number of Cu = 29, Ni = 28, Mn = 25, Fe = 26]

Correct answer: 6
Question 59
Mathematics · 4 marks · −1Consider the following two statements : Statement I : For any two non-zero complex numbers , , and Statement II : If x, y, z are three distinct complex numbers and a, b, c are three positive real numbers such that , then . Between the above two statements,
- A.Statement I is correct but Statement II is incorrect.
- B.both Statement I and Statement II are correct.
- C.both Statement I and Statement II are incorrect.
- D.Statement I is incorrect but Statement II is correct.
Correct answer: A
Explanation: I holds since the unit-vector sum has modulus at most 2; II fails (the sum is 0, not 1).
Question 60
Mathematics · 4 marks · −1If and , then the point (m, n) lies on the line
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: , .
Question 61
Mathematics · 4 marks · −1Suppose is a solution of . Then is equal to :
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: .
Question 62
Mathematics · 4 marks · −1Let two straight lines drawn from the origin O intersect the line 3x + 4y = 12 at the points P and Q such that △OPQ is an isosceles triangle and ∠POQ = 90°. If , then the greatest integer less than or equal to l is :
- A.42
- B.46
- C.44
- D.48
Correct answer: B
Explanation: Altitude ; .
Question 63
Mathematics · 4 marks · −1If A(1, −1, 2), B(5, 7, −6), C(3, 4, −10) and D(−1, −4, −2) are the vertices of a quadrilateral ABCD, then its area is :
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: .
Question 64
Mathematics · 4 marks · −1Let a circle C of radius 1 and closer to the origin be such that the lines passing through the point (3, 2) and parallel to the coordinate axes touch it. Then the shortest distance of the circle C from the point (5, 5) is :
- A.
- B.
- C.4
- D.5
Correct answer: C
Explanation: Centre (2, 1); distance to (5, 5) is 5, minus radius 1.
Question 65
Mathematics · 4 marks · −1Let the line 2x + 3y − k = 0, k > 0, intersect the x-axis and y-axis at the points A and B, respectively. If the equation of the circle having the line segment AB as a diameter is and the length of the latus rectum of the ellipse is , where m and n are coprime, then 2m + n is equal to
- A.11
- B.10
- C.12
- D.13
Correct answer: A
Explanation: ; ellipse has latus rectum .
Question 66
Mathematics · 4 marks · −1Let A and B be two square matrices of order 3 such that |A| = 3 and |B| = 2. Then is equal to :
- A.108
- B.32
- C.81
- D.64
Correct answer: D
Explanation: .
Question 67
Mathematics · 4 marks · −1If the system of equations , , has infinitely many solutions, then is equal to :
- A.51
- B.45
- C.47
- D.49
Correct answer: C
Explanation: ; gives .
Question 68
Mathematics · 4 marks · −1Let A = {1, 3, 7, 9, 11} and B = {2, 4, 5, 7, 8, 10, 12}. Then the total number of one-one maps f : A → B, such that f(1) + f(3) = 14, is :
- A.480
- B.240
- C.120
- D.180
Correct answer: B
Explanation: 4 ordered choices for (f(1), f(3)), then .
Question 69
Mathematics · 4 marks · −1Let , , and g(x) be a function such that g(f(x)) = x for all . Then is equal to :
- A.14
- B.42
- C.7
- D.1
Correct answer: A
Explanation: , .
Question 70
Mathematics · 4 marks · −1If the function , , is continuous at x = 0, then f(0) is equal to :
- A.2
- B.−2
- C.4
- D.−4
Correct answer: D
Explanation: , ; the coefficient is .
Question 71
Mathematics · 4 marks · −1Let a rectangle ABCD of sides 2 and 4 be inscribed in another rectangle PQRS such that the vertices of the rectangle ABCD lie on the sides of the rectangle PQRS. Let a and b be the sides of the rectangle PQRS when its area is maximum. Then is equal to :
- A.72
- B.60
- C.64
- D.80
Correct answer: A
Explanation: At θ = 45°: .
Question 72
Mathematics · 4 marks · −1For the function , where , consider the following two statements : (I) f is increasing in . (II) f′ is decreasing in . Between the above two statements,
- A.only (II) is true.
- B.only (I) is true.
- C.neither (I) nor (II) is true.
- D.both (I) and (II) are true
Correct answer: D
Explanation: and .
Question 73
Mathematics · 4 marks · −1The value of is :
- A.
- B.
- C.
- D.
Correct answer: D
Explanation: Odd part vanishes; .
Question 74
Mathematics · 4 marks · −1The integral is equal to :
- A.
- B.
- C.
- D.
Correct answer: A
Explanation: .
Question 75
Mathematics · 4 marks · −1If y = y(x) is the solution of the differential equation , , then is equal to:
- A.
- B.
- C.
- D.
Correct answer: C
Explanation: .
Question 76
Mathematics · 4 marks · −1If the line makes a right angle with the line , then is equal to :
- A.4
- B.13
- C.5
- D.6
Correct answer: D
Explanation: Directions and : .
Question 77
Mathematics · 4 marks · −1Let d be the distance of the point of intersection of the lines and from the point (7, 8, 9). Then is equal to :
- A.69
- B.78
- C.72
- D.75
Correct answer: D
Explanation: Intersection (3, 6, 2); .
Question 78
Mathematics · 4 marks · −1The coefficients a, b, c in the quadratic equation are chosen from the set {1, 2, 3, 4, 5, 6, 7, 8}. The probability of this equation having repeated roots is :
- A.
- B.
- C.
- D.
Correct answer: B
Explanation: has 8 solutions out of 512.
Question 79
Mathematics · 4 marks · −1The number of ways of getting a sum 16 on throwing a dice four times is ______
Correct answer: 125
Explanation: .
Question 80
Mathematics · 4 marks · −1Let be in an arithmetic progression of positive terms. Let . If , and , then is equal to ______
Correct answer: 910
Explanation: gives , ; , .
Question 81
Mathematics · 4 marks · −1If the constant term in the expansion of is p, then 108p is equal to
Correct answer: 54
Explanation: .
Question 82
Mathematics · 4 marks · −1Suppose AB is a focal chord of the parabola of length l and slope . If the distance of the chord AB from the origin is d, then is equal to _______
Correct answer: 108
Explanation: , .
Question 83
Mathematics · 4 marks · −1Let f be a differentiable function in the interval (0, ∞) such that f(1) = 1 and for each x > 0. Then 2f(2) + 3f(3) is equal to _______
Correct answer: 24
Explanation: gives .
Question 84
Mathematics · 4 marks · −1From a lot of 10 items, which include 3 defective items, a sample of 5 items is drawn at random. Let the random variable X denote the number of defective items in the sample. If the variance of X is , then is equal to ______
Correct answer: 56
Explanation: Hypergeometric: .
Question 85
Mathematics · 4 marks · −1The number of distinct real roots of the equation |x||x + 2| − 5|x + 1| − 1 = 0 is _______
Correct answer: 3
Explanation: With : has roots and .
Question 86
Mathematics · 4 marks · −1If , where [t] denotes the greatest integer less than or equal to t and {t} represents the fractional part of t, then is equal to ______
Correct answer: 18
Explanation: Only .
Question 87
Mathematics · 4 marks · −1The area of the region enclosed by the parabolas and is
Correct answer: 72
Explanation: .
Question 88
Mathematics · 4 marks · −1Let , and be a vector such that . If , then is equal to _______
Correct answer: 30
Explanation: : .