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JEE Main 2024 Jan 31 Shift 2 — Question Paper

90 questions

Mathematics

Q1JEE Main 2024 Jan 31 Shift 2Sets, Relations and FunctionsMedium

If the function f:(āˆ’āˆž,āˆ’1]→(a,b]f:(-\infty,-1] \rightarrow(a, b] defined by f(x)=ex3āˆ’3x+1f(x)=e^{x^{3}-3 x+1} is one - one and onto, then the distance of the point P(2b+4,a+2)P(2 b+4, a+2) from the line x+eāˆ’3y=4x+e^{-3} y=4 is :

  1. A

    41+e64 \sqrt{1+e^{6}}

  2. B

    31+e63 \sqrt{1+e^{6}}

  3. C

    21+e62 \sqrt{1+e^{6}}

  4. D

    1+e6\sqrt{1+e^{6}}

Show answer

Correct option: C

Q2JEE Main 2024 Jan 31 Shift 2Trigonometric Ratios and EquationsMedium

The number of solutions, of the equation esin⁔xāˆ’2eāˆ’sin⁔x=2e^{\sin x}-2 e^{-\sin x}=2, is :

  1. A

    0

  2. B

    1

  3. C

    2

  4. D

    more than 2

Show answer

Correct option: A

Q3JEE Main 2024 Jan 31 Shift 2Complex NumbersMedium

Let z1z_{1} and z2z_{2} be two complex numbers such that z1+z2=5z_{1}+z_{2}=5 and z13+z23=20+15iz_{1}^{3}+z_{2}^{3}=20+15 i. Then, ∣z14+z24∣\left|z_{1}^{4}+z_{2}^{4}\right| equals -

  1. A

    30330 \sqrt{3}

  2. B

    151515 \sqrt{15}

  3. C

    25325 \sqrt{3}

  4. D

    75

Show answer

Correct option: D

Q4JEE Main 2024 Jan 31 Shift 2Matrices and DeterminantsMedium

Let AA be a 3Ɨ33 \times 3 real matrix such that

A(101)=2(101),Ā A(āˆ’101)=4(āˆ’101),Ā A(010)=2(010).A\begin{pmatrix}1 \\ 0 \\ 1\end{pmatrix}=2\begin{pmatrix}1 \\ 0 \\ 1\end{pmatrix},\ A\begin{pmatrix}-1 \\ 0 \\ 1\end{pmatrix}=4\begin{pmatrix}-1 \\ 0 \\ 1\end{pmatrix},\ A\begin{pmatrix}0 \\ 1 \\ 0\end{pmatrix}=2\begin{pmatrix}0 \\ 1 \\ 0\end{pmatrix}.

Then, the system (Aāˆ’3I)(xyz)=(123)(A-3 I)\begin{pmatrix}x \\ y \\ z\end{pmatrix}=\begin{pmatrix}1 \\ 2 \\ 3\end{pmatrix} has

  1. A

    no solution

  2. B

    infinitely many solutions

  3. C

    unique solution

  4. D

    exactly two solutions

Show answer

Correct option: C

Q5JEE Main 2024 Jan 31 Shift 2Permutations and CombinationsEasy

The number of ways in which 21 identical apples can be distributed among three children such that each child gets at least 2 apples, is

  1. A

    130

  2. B

    136

  3. C

    142

  4. D

    406

Show answer

Correct option: B

Q6JEE Main 2024 Jan 31 Shift 2Permutations and CombinationsMedium

If for some m,nm, n; 6Cm+2(6Cm+1)+6Cm+2>8C3{ }^{6} C_{m}+2\left({ }^{6} C_{m+1}\right)+{ }^{6} C_{m+2}>{ }^{8} C_{3} and nāˆ’1P3:nP4=1:8{ }^{n-1} P_{3}:{ }^{n} P_{4}=1: 8, then nPm+1+n+1Cm{ }^{n} P_{m+1}+{ }^{\mathrm{n}+1} C_{m} is equal to

  1. A

    372

  2. B

    376

  3. C

    380

  4. D

    384

Show answer

Correct option: A

Q7JEE Main 2024 Jan 31 Shift 2Sequences and SeriesMedium

Let 2ndĀ ,8thĀ 2^{\text {nd }}, 8^{\text {th }} and 44thĀ 44^{\text {th }} terms of a non-constant A. P. be respectively the 1stĀ ,2ndĀ 1^{\text {st }}, 2^{\text {nd }} and 3rdĀ 3^{\text {rd }} terms of a G. P. If the first term of the A. P. is 1, then the sum of its first 20 terms is equal to -

  1. A

    960

  2. B

    970

  3. C

    980

  4. D

    990

Show answer

Correct option: B

Q8JEE Main 2024 Jan 31 Shift 2Limits, Continuity and DifferentiabilityMedium

Consider the function f:(0,āˆž)→Rf:(0, \infty) \rightarrow \mathbb{R} defined by f(x)=eāˆ’āˆ£log⁔ex∣f(x)=e^{-\left|\log _{e} x\right|}. If mm and nn be respectively the number of points at which ff is not continuous and ff is not differentiable, then m+nm+n is

  1. A

    0

  2. B

    1

  3. C

    2

  4. D

    3

Show answer

Correct option: B

Q9JEE Main 2024 Jan 31 Shift 2Limits, Continuity and DifferentiabilityMedium

Let f:R→(0,āˆž)f: \mathbb{R} \rightarrow(0, \infty) be strictly increasing function such that lim⁔xā†’āˆžf(7x)f(x)=1\lim _{x \rightarrow \infty} \frac{f(7 x)}{f(x)}=1. Then, the value of lim⁔xā†’āˆž[f(5x)f(x)āˆ’1]\lim _{x \rightarrow \infty}\left[\frac{f(5 x)}{f(x)}-1\right] is equal to

  1. A

    1

  2. B

    7/5

  3. C

    4

  4. D

    0

Show answer

Correct option: D

Q10JEE Main 2024 Jan 31 Shift 2CirclesMedium

Let a variable line passing through the centre of the circle x2+y2āˆ’16xāˆ’4y=0x^{2}+y^{2}-16 x-4 y=0, meet the positive co-ordinate axes at the points AA and BB. Then the minimum value of OA+OBOA+OB, where OO is the origin, is equal to

  1. A

    12

  2. B

    18

  3. C

    20

  4. D

    24

Show answer

Correct option: B

Q11JEE Main 2024 Jan 31 Shift 2Integral CalculusMedium

The area of the region enclosed by the parabolas y=4xāˆ’x2y=4 x-x^{2} and 3y=(xāˆ’4)23 y=(x-4)^{2} is equal to

  1. A

    143\frac{14}{3}

  2. B

    6

  3. C

    329\frac{32}{9}

  4. D

    4

Show answer

Correct option: B

Q12JEE Main 2024 Jan 31 Shift 2Integral CalculusHard

Let f,g:(0,āˆž)→Rf, g:(0, \infty) \rightarrow \mathbb{R} be two functions defined by f(x)=āˆ«āˆ’xx(∣tāˆ£āˆ’t2)eāˆ’t2dtf(x)=\int_{-x}^{x}\left(|t|-t^{2}\right) e^{-t^{2}} d t and g(x)=∫0x2t1/2eāˆ’tdtg(x)=\int_{0}^{x^{2}} t^{1 / 2} e^{-t} d t. Then, the value of 9(f(log⁔e9)+g(log⁔e9))9\left(f\left(\sqrt{\log _{e} 9}\right)+g\left(\sqrt{\log _{e} 9}\right)\right) is equal to

  1. A

    8

  2. B

    6

  3. C

    9

  4. D

    10

Show answer

Correct option: A

Q13JEE Main 2024 Jan 31 Shift 2Differential EquationsMedium

The temperature T(t)T(t) of a body at time t=0t=0 is 160∘F160^{\circ} \mathrm{F} and it decreases continuously as per the differential equation dTdt=āˆ’K(Tāˆ’80)\frac{d T}{d t}=-K(T-80), where KK is a positive constant. If T(15)=120∘FT(15)=120^{\circ} \mathrm{F}, then T(45)T(45) is equal to

  1. A

    80∘F80^{\circ} \mathrm{F}

  2. B

    85∘F85^{\circ} \mathrm{F}

  3. C

    90∘F90^{\circ} \mathrm{F}

  4. D

    95∘F95^{\circ} \mathrm{F}

Show answer

Correct option: C

Q14JEE Main 2024 Jan 31 Shift 2Conic SectionsHard

Let PP be a parabola with vertex (2,3)(2,3) and directrix 2x+y=62 x+y=6. Let an ellipse E:x2a2+y2b2=1,a>bE: \frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}}=1, a>b, of eccentricity 12\frac{1}{\sqrt{2}} pass through the focus of the parabola PP. Then, the square of the length of the latus rectum of EE, is

  1. A

    51225\frac{512}{25}

  2. B

    3858\frac{385}{8}

  3. C

    65625\frac{656}{25}

  4. D

    3478\frac{347}{8}

Show answer

Correct option: C

Q15JEE Main 2024 Jan 31 Shift 2Straight LinesHard

Let A(a,b),B(3,4)A(a, b), B(3,4) and C(āˆ’6,āˆ’8)C(-6,-8) respectively denote the centroid, circumcentre and orthocentre of a triangle. Then, the distance of the point P(2a+3,7b+5)P(2 a+3,7 b+5) from the line 2x+3yāˆ’4=02 x+3 y-4=0 measured parallel to the line xāˆ’2yāˆ’1=0x-2 y-1=0 is

  1. A

    517\frac{\sqrt{5}}{17}

  2. B

    1757\frac{17 \sqrt{5}}{7}

  3. C

    1557\frac{15 \sqrt{5}}{7}

  4. D

    1756\frac{17 \sqrt{5}}{6}

Show answer

Correct option: B

Q16JEE Main 2024 Jan 31 Shift 2Three Dimensional GeometryMedium

Let (α,β,γ)(\alpha, \beta, \gamma) be the mirror image of the point (2,3,5)(2,3,5) in the line xāˆ’12=yāˆ’23=zāˆ’34\frac{x-1}{2}=\frac{y-2}{3}=\frac{z-3}{4}. Then, 2α+3β+4γ2 \alpha+3 \beta+4 \gamma is equal to

  1. A

    31

  2. B

    32

  3. C

    33

  4. D

    34

Show answer

Correct option: C

Q17JEE Main 2024 Jan 31 Shift 2Three Dimensional GeometryHard

The shortest distance, between lines L1L_{1} and L2L_{2}, where L1:xāˆ’12=y+1āˆ’3=z+42L_{1}: \frac{x-1}{2}=\frac{y+1}{-3}=\frac{z+4}{2} and L2L_{2} is the line, passing through the points A(āˆ’4,4,3),B(āˆ’1,6,3)\mathrm{A}(-4,4,3), \mathrm{B}(-1,6,3) and perpendicular to the line xāˆ’3āˆ’2=y3=zāˆ’11\frac{x-3}{-2}=\frac{y}{3}=\frac{z-1}{1}, is

  1. A

    24117\frac{24}{\sqrt{117}}

  2. B

    42117\frac{42}{\sqrt{117}}

  3. C

    121221\frac{121}{\sqrt{221}}

  4. D

    141221\frac{141}{\sqrt{221}}

Show answer

Correct option: D

Q18JEE Main 2024 Jan 31 Shift 2StatisticsMedium

Let the mean and the variance of 6 observations a,b,68,44,48,60a, b, 68,44,48,60 be 55 and 194, respectively. If a>ba>b, then a+3ba+3 b is

  1. A

    180

  2. B

    190

  3. C

    200

  4. D

    210

Show answer

Correct option: A

Q19JEE Main 2024 Jan 31 Shift 2ProbabilityEasy

A coin is biased so that a head is twice as likely to occur as a tail. If the coin is tossed 3 times, then the probability of getting two tails and one head is

  1. A

    127\frac{1}{27}

  2. B

    227\frac{2}{27}

  3. C

    19\frac{1}{9}

  4. D

    29\frac{2}{9}

Show answer

Correct option: D

Q20JEE Main 2024 Jan 31 Shift 2Inverse Trigonometric FunctionsMedium

If a=sinā”āˆ’1(sin⁔(5))a=\sin ^{-1}(\sin (5)) and b=cosā”āˆ’1(cos⁔(5))b=\cos ^{-1}(\cos (5)), then a2+b2a^{2}+b^{2} is equal to

  1. A

    25

  2. B

    4Ļ€2+254 \pi^{2}+25

  3. C

    4Ļ€2āˆ’20Ļ€+504 \pi^{2}-20 \pi+50

  4. D

    8Ļ€2āˆ’40Ļ€+508 \pi^{2}-40 \pi+50

Show answer

Correct option: D

Q21JEE Main 2024 Jan 31 Shift 2Sets, Relations and FunctionsMediumNumerical

Let A={1,2,3,………,100}A=\{1,2,3, \ldots \ldots \ldots, 100\}. Let RR be a relation on A defined by (x,y)∈R(x, y) \in R if and only if 2x=3y2 x=3 y. Let R1R_{1} be a symmetric relation on AA such that RāŠ‚R1R \subset R_{1} and the number of elements in R1R_{1} is n. Then, the minimum value of n is _________.

Show answer

Answer: 66

Q22JEE Main 2024 Jan 31 Shift 2Matrices and DeterminantsHardNumerical

Let A be a 3Ɨ33 \times 3 matrix and det⁔(A)=2\det(A)=2. If n=det⁔(adj(adj(……(adjĀ A)))āŸ2024āˆ’times)n=\det (\underbrace{a d j\left(a d j\left(\ldots \ldots(a d j\ A)\right)\right)}_{2024-\text{times}}), then the remainder when nn is divided by 9 is equal to ________.

Show answer

Answer: 7

Q23JEE Main 2024 Jan 31 Shift 2Binomial TheoremMediumNumerical

Let the coefficient of xrx^{r} in the expansion of (x+3)nāˆ’1+(x+3)nāˆ’2(x+2)+(x+3)nāˆ’3(x+2)2+………+(x+2)nāˆ’1(x+3)^{n-1}+(x+3)^{n-2}(x+2)+(x+3)^{n-3}(x+2)^{2}+\ldots \ldots \ldots+(x+2)^{n-1} be αr\alpha_{r}. If āˆ‘r=0nαr=βnāˆ’Ī³n\sum_{r=0}^{n} \alpha_{r}=\beta^{n}-\gamma^{n}, β,γ∈N\beta, \gamma \in \mathbb{N}, then the value of β2+γ2\beta^{2}+\gamma^{2} equals ________.

Show answer

Answer: 25

Q24JEE Main 2024 Jan 31 Shift 2Quadratic EquationsHardNumerical

Let a,b,ca, b, c be the lengths of three sides of a triangle satisfying the condition (a2+b2)x2āˆ’2b(a+c)x+(b2+c2)=0\left(a^{2}+b^{2}\right) x^{2}-2 b(a+c) x+\left(b^{2}+c^{2}\right)=0. If the set of all possible values of xx is the interval (α,β)(\alpha, \beta), then 12(α2+β2)12\left(\alpha^{2}+\beta^{2}\right) is equal to ______.

Show answer

Answer: 36

Q25JEE Main 2024 Jan 31 Shift 2Limits, Continuity and DifferentiabilityHardNumerical

If lim⁔x→0ax2exāˆ’blog⁔e(1+x)+cxeāˆ’xx2sin⁔x=1\lim _{x \rightarrow 0} \frac{a x^{2} e^{x}-b \log _{e}(1+x)+c x e^{-x}}{x^{2} \sin x}=1, then 16(a2+b2+c2)16\left(a^{2}+b^{2}+c^{2}\right) is equal to ______.

Show answer

Answer: 81

Q26JEE Main 2024 Jan 31 Shift 2Integral CalculusHardNumerical

∣120Ļ€3∫0Ļ€x2sin⁔xcos⁔xsin⁔4x+cos⁔4xĀ dx∣\left|\frac{120}{\pi^{3}} \int_{0}^{\pi} \frac{x^{2} \sin x \cos x}{\sin ^{4} x+\cos ^{4} x}\ d x\right| is equal to ________.

Show answer

Answer: 15

Q27JEE Main 2024 Jan 31 Shift 2Differential EquationsHardNumerical

Let y=y(x)y=y(x) be the solution of the differential equation sec⁔2xĀ dx+(e2ytan⁔2x+tan⁔x)dy=0\sec ^{2} x\ d x+\left(e^{2 y} \tan ^{2} x+\tan x\right) d y=0, 0<x<Ļ€20<x<\frac{\pi}{2}, y(Ļ€/4)=0y\left(\pi / 4\right)=0. If y(Ļ€/6)=αy\left(\pi / 6\right)=\alpha, then e8αe^{8 \alpha} is equal to _______.

Show answer

Answer: 9

Q28JEE Main 2024 Jan 31 Shift 2Straight LinesMediumNumerical

Let A(āˆ’2,āˆ’1),B(1,0),C(α,β)A(-2,-1), B(1,0), C(\alpha, \beta) and D(γ,Ī“)D(\gamma, \delta) be the vertices of a parallelogram ABCDABCD. If the point CC lies on 2xāˆ’y=52 x-y=5 and the point DD lies on 3xāˆ’2y=63 x-2 y=6, then the value of ∣α+β+γ+Γ∣|\alpha+\beta+\gamma+\delta| is equal to ________.

Show answer

Answer: 32

Q29JEE Main 2024 Jan 31 Shift 2Three Dimensional GeometryMediumNumerical

A line passes through A(4,āˆ’6,āˆ’2)A(4,-6,-2) and B(16,āˆ’2,4)B(16,-2,4). The point P(a,b,c)P(a, b, c), where a,b,ca, b, c are non-negative integers, on the line ABAB lies at a distance of 21 units, from the point AA. The distance between the points P(a,b,c)P(a, b, c) and Q(4,āˆ’12,3)Q(4,-12,3) is equal to __________.

Show answer

Answer: 22

Q30JEE Main 2024 Jan 31 Shift 2Vector AlgebraHardNumerical

Let aāƒ—=3i^+2j^+k^\vec{a}=3 \hat{i}+2 \hat{j}+\hat{k}, bāƒ—=2i^āˆ’j^+3k^\vec{b}=2 \hat{i}-\hat{j}+3 \hat{k} and cāƒ—\vec{c} be a vector such that (aāƒ—+bāƒ—)Ɨcāƒ—=2(aāƒ—Ć—bāƒ—)+24j^āˆ’6k^(\vec{a}+\vec{b}) \times \vec{c}=2(\vec{a} \times \vec{b})+24 \hat{j}-6 \hat{k} and (aāƒ—āˆ’bāƒ—+i^)ā‹…cāƒ—=āˆ’3(\vec{a}-\vec{b}+\hat{i}) \cdot \vec{c}=-3. Then ∣cāƒ—āˆ£2|\vec{c}|^{2} is equal to ______.

Show answer

Answer: 38

Physics

Q31JEE Main 2024 Jan 31 Shift 2Units and MeasurementsMedium

Consider two physical quantities AA and BB related to each other as E=Bāˆ’x2AtE = \frac{B - x^2}{At} where EE, xx and tt have dimensions of energy, length and time respectively. The dimension of ABAB is

  1. A

    L0Māˆ’1T1L^{0}M^{-1}T^{1}

  2. B

    L2Māˆ’1T1L^{2}M^{-1}T^{1}

  3. C

    Lāˆ’2M1T0L^{-2}M^{1}T^{0}

  4. D

    Lāˆ’2Māˆ’1T1L^{-2}M^{-1}T^{1}

Show answer

Correct option: B

Q32JEE Main 2024 Jan 31 Shift 2KinematicsEasy

If two vectors Aāƒ—\vec{A} and Bāƒ—\vec{B} having equal magnitude RR are inclined at an angle Īø\theta, then

  1. A

    ∣Aāƒ—+Bāƒ—āˆ£=2Rsin⁔(Īø2)\left|\vec{A} + \vec{B}\right| = 2R\sin\left(\frac{\theta}{2}\right)

  2. B

    ∣Aāƒ—āˆ’Bāƒ—āˆ£=2Rcos⁔(Īø2)\left|\vec{A} - \vec{B}\right| = 2R\cos\left(\frac{\theta}{2}\right)

  3. C

    ∣Aāƒ—+Bāƒ—āˆ£=2Rcos⁔(Īø2)\left|\vec{A} + \vec{B}\right| = 2R\cos\left(\frac{\theta}{2}\right)

  4. D

    ∣Aāƒ—āˆ’Bāƒ—āˆ£=2 Rsin⁔(Īø2)\left|\vec{A} - \vec{B}\right| = \sqrt{2}\,R\sin\left(\frac{\theta}{2}\right)

Show answer

Correct option: C

Q33JEE Main 2024 Jan 31 Shift 2Laws of MotionEasy

A light string passing over a smooth light fixed pulley connects two blocks of masses m1m_1 and m2m_2. If the acceleration of the system is g/8g/8, then the ratio of masses is:

[Figure: a fixed pulley attached to the ceiling with masses m1m_1 and m2m_2 hanging on either side of the string]

  1. A

    43\frac{4}{3}

  2. B

    53\frac{5}{3}

  3. C

    81\frac{8}{1}

  4. D

    97\frac{9}{7}

Show answer

Correct option: D

Q34JEE Main 2024 Jan 31 Shift 2Laws of MotionMedium

[Figure: a 5 kg block on an inclined plane of angle 30°30° with coefficient of friction μ=0.1\mu = 0.1]

A block of mass 5 kg is placed on a rough inclined surface as shown in the figure. If F1āƒ—\vec{F_1} is the force required to just move the block up the inclined plane and F2āƒ—\vec{F_2} is the force required to just prevent the block from sliding down, then the value of ∣F1āƒ—āˆ£āˆ’āˆ£F2āƒ—āˆ£\left|\vec{F_1}\right| - \left|\vec{F_2}\right| is: [Use g = 10 m/s2^2]

  1. A

    532Ā N\frac{5\sqrt{3}}{2}\ N

  2. B

    10Ā N10\ N

  3. C

    253Ā N25\sqrt{3}\ N

  4. D

    503Ā N50\sqrt{3}\ N

Q35JEE Main 2024 Jan 31 Shift 2Work, Energy and PowerMedium

A body of mass 2 kg begins to move under the action of a time dependent force given by Fāƒ—=(6t i^+6t2 j^)N\vec{F} = \left(6t\,\hat{i} + 6t^2\,\hat{j}\right) N. The power developed by the force at the time tt is given by:

  1. A

    (6t4+9t5)Ā W(6t^4 + 9t^5)\ W

  2. B

    (9t5+6t3)Ā W(9t^5 + 6t^3)\ W

  3. C

    (3t3+6t5)Ā W(3t^3 + 6t^5)\ W

  4. D

    (9t3+6t5)Ā W(9t^3 + 6t^5)\ W

Show answer

Correct option: D

Q36JEE Main 2024 Jan 31 Shift 2GravitationMedium

The mass of the moon is 1144\frac{1}{144} times the mass of a planet and its diameter is 116\frac{1}{16} times the diameter of a planet. If the escape velocity on the planet is v, the escape velocity on the moon will be :

  1. A

    v12\frac{v}{12}

  2. B

    v4\frac{v}{4}

  3. C

    v6\frac{v}{6}

  4. D

    v3\frac{v}{3}

Show answer

Correct option: D

Q37JEE Main 2024 Jan 31 Shift 2Properties of Solids and LiquidsMedium

A small spherical ball of radius rr, falling through a viscous medium of negligible density has terminal velocity 'v'. Another ball of the same mass but of radius 2r2r, falling through the same viscous medium will have terminal velocity:

  1. A

    v2\frac{v}{2}

  2. B

    v4\frac{v}{4}

  3. C

    2v2v

  4. D

    4v4v

Show answer

Correct option: A

Q38JEE Main 2024 Jan 31 Shift 2WavesMedium

The speed of sound in oxygen at S.T.P. will be approximately:

(given, R=8.3Ā JKāˆ’1R = 8.3\ \mathrm{JK^{-1}}, γ=1.4\gamma = 1.4)

  1. A

    341Ā m/s341\ m/s

  2. B

    333Ā m/s333\ m/s

  3. C

    325Ā m/s325\ m/s

  4. D

    310Ā m/s310\ m/s

Show answer

Correct option: D

Q39JEE Main 2024 Jan 31 Shift 2Kinetic Theory of GasesMedium

A gas mixture consists of 8 moles of argon and 6 moles of oxygen at temperature T. Neglecting all vibrational modes, the total internal energy of the system is:

  1. A

    21Ā RT21\ RT

  2. B

    27Ā RT27\ RT

  3. C

    29Ā RT29\ RT

  4. D

    20Ā RT20\ RT

Show answer

Correct option: B

Q40JEE Main 2024 Jan 31 Shift 2ElectrostaticsEasy

Force between two point charges q1q_1 and q2q_2 placed in vacuum at 'rr' cm apart is FF. Force between them when placed in a medium having dielectric constant K=5K=5 at 'r/5r/5' cm apart will be:

  1. A

    F/5F/5

  2. B

    5F5F

  3. C

    F/25F/25

  4. D

    25F25F

Show answer

Correct option: B

Q41JEE Main 2024 Jan 31 Shift 2Current ElectricityMedium

By what percentage will the illumination of the lamp decrease if the current drops by 20%?

  1. A

    36%36\%

  2. B

    46%46\%

  3. C

    56%56\%

  4. D

    26%26\%

Show answer

Correct option: A

Q42JEE Main 2024 Jan 31 Shift 2Magnetic Effects of Current and MagnetismMedium

A uniform magnetic field of 2Ɨ10āˆ’3Ā T2 \times 10^{-3}\ T acts along positive YY-direction. A rectangular loop of sides 20 cm and 10 cm with current of 5Ā A5\ A is in YY–ZZ plane. The current is in anticlockwise sense with reference to negative XX axis. Magnitude and direction of the torque is:

  1. A

    2Ɨ10āˆ’4Ā N-m2 \times 10^{-4}\ N\text{-}m along positive ZZ-direction

  2. B

    2Ɨ10āˆ’4Ā N-m2 \times 10^{-4}\ N\text{-}m along negative ZZ-direction

  3. C

    2Ɨ10āˆ’4Ā N-m2 \times 10^{-4}\ N\text{-}m along positive YY-direction

  4. D

    2Ɨ10āˆ’4Ā N-m2 \times 10^{-4}\ N\text{-}m along positive XX-direction

Show answer

Correct option: B

Q43JEE Main 2024 Jan 31 Shift 2Electromagnetic Induction and Alternating CurrentsMedium

An AC voltage V=20sin⁔200Ļ€tV = 20 \sin 200\pi t is applied to a series LCR circuit which drives a current I=10sin⁔(200 πt+Ļ€3)I = 10 \sin\left(200\,\pi t + \frac{\pi}{3}\right). The average power dissipated is:

  1. A

    21.6Ā W21.6\ W

  2. B

    200Ā W200\ W

  3. C

    50Ā W50\ W

  4. D

    173.2Ā W173.2\ W

Show answer

Correct option: C

Q44JEE Main 2024 Jan 31 Shift 2Electromagnetic WavesEasy

Given below are two statements:

Statement I: Electromagnetic waves carry energy as they travel through space and this energy is equally shared by the electric and magnetic fields.

Statement II: When electromagnetic waves strike a surface, a pressure is exerted on the surface.

In the light of the above statements, choose the most appropriate answer from the options given below:

  1. A

    Both Statement I and Statement II are correct.

  2. B

    Both Statement I and Statement II are incorrect.

  3. C

    Statement I is correct but Statement II is incorrect.

  4. D

    Statement I is incorrect but Statement II is correct.

Show answer

Correct option: A

Q45JEE Main 2024 Jan 31 Shift 2Wave OpticsEasy

When unpolarized light is incident at an angle of 60°60° on a transparent medium from air, the reflected ray is completely polarized. The angle of refraction in the medium is:

  1. A

    30°30°

  2. B

    60°60°

  3. C

    45°45°

  4. D

    90°90°

Show answer

Correct option: A

Q46JEE Main 2024 Jan 31 Shift 2Dual Nature of Matter and RadiationEasy

In a photoelectric effect experiment a light of frequency 1.5 times the threshold frequency is made to fall on the surface of photosensitive material. Now if the frequency is halved and intensity is doubled, the number of photo electrons emitted will be:

  1. A

    Zero

  2. B

    halved

  3. C

    doubled

  4. D

    quadrupled

Show answer

Correct option: A

Q47JEE Main 2024 Jan 31 Shift 2Atoms and NucleiEasy

The mass number of nucleus having radius equal to half of the radius of nucleus with mass number 192 is:

  1. A

    2020

  2. B

    3232

  3. C

    2424

  4. D

    4040

Show answer

Correct option: C

Q48JEE Main 2024 Jan 31 Shift 2Electronic DevicesMedium

[Figure: logic circuit — inputs A and B; A and NOT(B) feed an OR gate; B and NOT(A) feed a second OR gate; the two OR outputs feed a NOR gate whose output is Y]

The output of the given circuit diagram is -

  1. A

    Truth table: | A | B | Y |; 0 0 0; 1 0 1; 0 1 1; 1 1 0

  2. B

    Truth table: | A | B | Y |; 0 0 0; 1 0 0; 0 1 0; 1 1 0

  3. C

    Truth table: | A | B | Y |; 0 0 0; 1 0 0; 0 1 1; 1 1 0

  4. D

    Truth table: | A | B | Y |; 0 0 0; 1 0 0; 0 1 0; 1 1 1

Show answer

Correct option: B

Q49JEE Main 2024 Jan 31 Shift 2Experimental SkillsMedium

The resistance per centimeter of a meter bridge wire is rr, with X ΩX\ \Omega resistance in left gap. Balancing length from left end is at 40 cm with 25 Ω25\ \Omega resistance in right gap. Now the wire is replaced by another wire of 2r2r resistance per centimeter. The new balancing length for same settings will be at

  1. A

    80Ā cm80\ \mathrm{cm}

  2. B

    20Ā cm20\ \mathrm{cm}

  3. C

    10Ā cm10\ \mathrm{cm}

  4. D

    40Ā cm40\ \mathrm{cm}

Show answer

Correct option: D

Q50JEE Main 2024 Jan 31 Shift 2Units and MeasurementsMedium

The measured value of the length of a simple pendulum is 20 cm with 2 mm accuracy. The time for 50 oscillations was measured to be 40 seconds with 1 second resolution. From these measurements, the accuracy in the measurement of acceleration due to gravity is N%. The value of N is:

  1. A

    66

  2. B

    44

  3. C

    88

  4. D

    55

Show answer

Correct option: A

Q51JEE Main 2024 Jan 31 Shift 2Rotational MotionMediumNumerical

A body of mass 'mm' is projected with a speed 'uu' making an angle of 45°45° with the ground. The angular momentum of the body about the point of projection, at the highest point is expressed as 2 mu3Xg\frac{\sqrt{2}\,mu^3}{Xg}. The value of 'XX' is ________.

Show answer

Answer: 8

Q52JEE Main 2024 Jan 31 Shift 2Rotational MotionMediumNumerical

Two identical spheres each of mass 2 kg and radius 50 cm are fixed at the ends of a light rod so that the separation between the centers is 150 cm. Then, moment of inertia of the system about an axis perpendicular to the rod and passing through its middle point is x20Ā kgĀ m2\frac{x}{20}\ kg\ m^2, where the value of xx is ________.

Show answer

Answer: 53

Q53JEE Main 2024 Jan 31 Shift 2Properties of Solids and LiquidsMediumNumerical

Two blocks of mass 2 kg and 4 kg are connected by a metal wire going over a smooth pulley as shown in figure. The radius of wire is 4.0Ɨ10āˆ’54.0 \times 10^{-5} m and Young's modulus of the metal is 2.0Ɨ10112.0 \times 10^{11} N/m2^2. The longitudinal strain developed in the wire is 1απ\frac{1}{\alpha\pi}. The value of α\alpha is ________. [Use g=10g = 10 m/s2^2]

[Figure: a smooth pulley fixed to the ceiling with a 2 kg block and a 4 kg block hanging from the two ends of the wire]

Show answer

Answer: 12

Q54JEE Main 2024 Jan 31 Shift 2OscillationsMediumNumerical

The time period of simple harmonic motion of mass MM in the given figure is παM5k\pi\sqrt{\frac{\alpha M}{5k}}, where the value of α\alpha is ________.

[Figure: mass M suspended from the ceiling by a combination of springs — two springs of constant k in parallel, in series with another spring of constant k, all in parallel with a spring of constant k]

Show answer

Answer: 12

Q55JEE Main 2024 Jan 31 Shift 2ElectrostaticsHardNumerical

The distance between charges +q+q and āˆ’q-q is 2l2l and between +2q+2q and āˆ’2q-2q is 4l4l. The electrostatic potential at point PP at a distance rr from center OO is āˆ’Ī±[qlr2]Ɨ109Ā V-\alpha\left[\frac{ql}{r^2}\right] \times 10^9\ V, where the value of α\alpha is ________. (Use 14πε0=9Ɨ109Ā Nm2Cāˆ’2\frac{1}{4\pi\varepsilon_0} = 9 \times 10^9\ Nm^2C^{-2})

[Figure: charges +2q+2q, āˆ’q-q, +q+q, āˆ’2q-2q placed on a straight line with center OO; point PP at distance rr from OO along a line making 60°60° with the line of charges]

Show answer

Answer: 27

Q56JEE Main 2024 Jan 31 Shift 2Current ElectricityMediumNumerical

In the following circuit, the battery has an emf of 2V and an internal resistance of 23Ā Ī©\frac{2}{3}\ \Omega. The power consumption in the entire circuit is ________ W.

[Figure: a square network of 2Ā Ī©2\ \Omega resistors — four resistors along the sides/diagonals meeting at the center and one 2Ā Ī©2\ \Omega resistor at the bottom, connected to a 2 V battery with internal resistance 23Ā Ī©\frac{2}{3}\ \Omega]

Show answer

Answer: 3

Q57JEE Main 2024 Jan 31 Shift 2Magnetic Effects of Current and MagnetismMediumNumerical

Two circular coils PP and QQ of 100 turns each have same radius of π\pi cm. The currents in PP and RR are 1AA and 2AA respectively. PP and QQ are placed with their planes mutually perpendicular and their centers coincide. The resultant magnetic field induction at the center of the coils is x mT\sqrt{x}\ mT, where x=x = __________.

[Use μ0=4π×10āˆ’7Ā TmAāˆ’1\mu_0 = 4\pi \times 10^{-7}\ TmA^{-1}]

Show answer

Answer: 20

Q58JEE Main 2024 Jan 31 Shift 2Electromagnetic Induction and Alternating CurrentsEasyNumerical

The magnetic flux Ļ•\phi (in weber) linked with a closed circuit of resistance 8Ā Ī©8\ \Omega varies with time (in seconds) as Ļ•=5t2āˆ’36t+1\phi = 5t^2 - 36t + 1. The induced current in the circuit at t=2t = 2 s is ________ AA.

Show answer

Answer: 2

Q59JEE Main 2024 Jan 31 Shift 2Ray OpticsMediumNumerical

Light from a point source in air falls on a convex curved surface of radius 20 cm and refractive index 1.5. If the source is located at 100 cm from the convex surface, the image will be formed at ________ cm from the object.

Show answer

Answer: 200

Q60JEE Main 2024 Jan 31 Shift 2Atoms and NucleiEasyNumerical

A nucleus has mass number A1A_1 and volume V1V_1. Another nucleus has mass number A2A_2 and Volume V2V_2. If relation between mass number is A2=4A1A_2 = 4A_1, then V2V1=\frac{V_2}{V_1} = ________.

Show answer

Answer: 4

Chemistry

Q61JEE Main 2024 Jan 31 Shift 2Some Basic Concepts in ChemistryMedium

A sample of CaCO3\mathrm{CaCO_3} and MgCO3\mathrm{MgCO_3} weighed 2.21Ā g2.21\ \mathrm{g} is ignited to constant weight of 1.152Ā g1.152\ \mathrm{g}. The composition of mixture is :

(Given molar mass in gĀ molāˆ’1\mathrm{g\ mol^{-1}} CaCO3\mathrm{CaCO_3} : 100, MgCO3\mathrm{MgCO_3} : 84)

  1. A

    1.023Ā gĀ CaCO3+1.187Ā gĀ MgCO31.023\ \mathrm{g}\ \mathrm{CaCO_3} + 1.187\ \mathrm{g}\ \mathrm{MgCO_3}

  2. B

    1.187Ā gĀ CaCO3+1.023Ā gĀ MgCO31.187\ \mathrm{g}\ \mathrm{CaCO_3} + 1.023\ \mathrm{g}\ \mathrm{MgCO_3}

  3. C

    1.023Ā gĀ CaCO3+1.023Ā gĀ MgCO31.023\ \mathrm{g}\ \mathrm{CaCO_3} + 1.023\ \mathrm{g}\ \mathrm{MgCO_3}

  4. D

    1.187Ā gĀ CaCO3+1.187Ā gĀ MgCO31.187\ \mathrm{g}\ \mathrm{CaCO_3} + 1.187\ \mathrm{g}\ \mathrm{MgCO_3}

Show answer

Correct option: B

Q62JEE Main 2024 Jan 31 Shift 2Atomic StructureEasy

The four quantum numbers for the electron in the outer most orbital of potassium (atomic no. 19) are

  1. A

    n=2,Ā l=0,Ā m=0,Ā s=+12\mathrm{n} = 2,\ l = 0,\ \mathrm{m} = 0,\ s = +\frac{1}{2}

  2. B

    n=3,Ā l=0,Ā m=1,Ā s=+12\mathrm{n} = 3,\ l = 0,\ \mathrm{m} = 1,\ s = +\frac{1}{2}

  3. C

    n=4,Ā l=0,Ā m=0,Ā s=+12\mathrm{n} = 4,\ l = 0,\ \mathrm{m} = 0,\ s = +\frac{1}{2}

  4. D

    n=4,Ā l=2,Ā m=āˆ’1,Ā s=+12\mathrm{n} = 4,\ l = 2,\ \mathrm{m} = -1,\ s = +\frac{1}{2}

Show answer

Correct option: C

Q63JEE Main 2024 Jan 31 Shift 2Chemical Bonding and Molecular StructureEasy

Which of the following is least ionic?

  1. A

    KCl\mathrm{KCl}

  2. B

    AgCl\mathrm{AgCl}

  3. C

    BaCl2\mathrm{BaCl_2}

  4. D

    CoCl2\mathrm{CoCl_2}

Show answer

Correct option: B

Q64JEE Main 2024 Jan 31 Shift 2EquilibriumMedium

A(g)ā‡ŒB(g)+C2(g)\mathrm{A_{(g)}} \rightleftharpoons \mathrm{B_{(g)}} + \frac{\mathrm{C}}{2}_{\mathrm{(g)}} The correct relationship between KP\mathrm{K_P}, α\alpha and equilibrium pressure P\mathrm{P} is

  1. A

    KP=α3/2 P1/2(2+α)1/2(1āˆ’Ī±)\mathrm{K_P} = \dfrac{\alpha^{3/2}\,\mathrm{P}^{1/2}}{(2+\alpha)^{1/2}(1-\alpha)}

  2. B

    KP=α1/2 P1/2(2+α)1/2\mathrm{K_P} = \dfrac{\alpha^{1/2}\,\mathrm{P}^{1/2}}{(2+\alpha)^{1/2}}

  3. C

    KP=α1/2 P1/2(2+α)3/2\mathrm{K_P} = \dfrac{\alpha^{1/2}\,\mathrm{P}^{1/2}}{(2+\alpha)^{3/2}}

  4. D

    KP=α1/2 P3/2(2+α)3/2\mathrm{K_P} = \dfrac{\alpha^{1/2}\,\mathrm{P}^{3/2}}{(2+\alpha)^{3/2}}

Show answer

Correct option: A

Q65JEE Main 2024 Jan 31 Shift 2Redox Reactions and ElectrochemistryMedium

Given below are two statements :

Statement I : S8\mathrm{S_8} solid undergoes disproportionation reaction under alkaline conditions to form S2āˆ’\mathrm{S^{2-}} and S2O32āˆ’\mathrm{S_2O_3^{2-}}.

Statement II : ClO4āˆ’\mathrm{ClO_4^-} can undergo disproportionation reaction under acidic condition.

In the light of the above statements, choose the most appropriate answer from the options given below :

  1. A

    Both statement I and statement II are correct

  2. B

    Both statement I and statement II are incorrect

  3. C

    Statement I is correct but statement II is incorrect

  4. D

    Statement I is incorrect but statement II is correct

Show answer

Correct option: C

Q66JEE Main 2024 Jan 31 Shift 2Classification of Elements and PeriodicityMedium

Consider the following elements.

Group↓A′B′C′D′→Period\text{Group} \downarrow \quad \begin{matrix} \mathrm{A'} & \mathrm{B'} \\ \mathrm{C'} & \mathrm{D'} \end{matrix} \quad \rightarrow \text{Period}

(A′ and B′ lie in the same period with B′ to the right of A′; C′ and D′ lie in the next period directly below A′ and B′ respectively.)

Which of the following is/are true about A′, B′, C′ and D′?

A. Order of atomic radii: B′ < A′ < D′ < C′ B. Order of metallic character: B′ < A′ < D′ < C′ C. Size of the element: D′ < C′ < B′ < A′ D. Order of ionic radii: B′⁺ < A′⁺ < D′⁺ < C′⁺

Choose the correct answer from the options given below :

  1. A

    A, B and D only

  2. B

    A and B only

  3. C

    B, C and D only

  4. D

    A only

Show answer

Correct option: A

Q67JEE Main 2024 Jan 31 Shift 2p-Block ElementsMedium

Given below are two statements :

Statement I : Group 13 trivalent halides get easily hydrolyzed by water due to their covalent nature.

Statement II : AlCl3\mathrm{AlCl_3} upon hydrolysis in acidified aqueous solution forms octahedral [Al(H2O)6]3+\mathrm{[Al(H_2O)_6]^{3+}} ion.

In the light of the above statements, choose the correct answer from the options given below :

  1. A

    Both statement I and statement II are true

  2. B

    Both statement I and statement II are false

  3. C

    Statement I is true but statement II is false

  4. D

    Statement I is false but statement II is true

Show answer

Correct option: A

Q68JEE Main 2024 Jan 31 Shift 2p-Block ElementsMedium

Choose the correct statements from the following

A. All group 16 elements form oxides of general formula EO2\mathrm{EO_2} and EO3\mathrm{EO_3}, where E = S, Se, Te and Po. Both the types of oxides are acidic in nature. B. TeO2\mathrm{TeO_2} is an oxidising agent while SO2\mathrm{SO_2} is reducing in nature. C. The reducing property decreases from H2S\mathrm{H_2S} to H2Te\mathrm{H_2Te} down the group. D. The ozone molecule contains five lone pairs of electrons.

Choose the correct answer from the options given below:

  1. A

    B and C only

  2. B

    A and B only

  3. C

    A and D only

  4. D

    C and D only

Show answer

Correct option: B

Q69JEE Main 2024 Jan 31 Shift 2d- and f-Block ElementsMedium

Choose the correct statements from the following

A. Mn2O7\mathrm{Mn_2O_7} is an oil at room temperature B. V2O4\mathrm{V_2O_4} reacts with acid to give VO22+\mathrm{VO_2^{2+}} C. CrO\mathrm{CrO} is a basic oxide D. V2O5\mathrm{V_2O_5} does not react with acid

Choose the correct answer from the options given below :

  1. A

    B and C only

  2. B

    A, B and C only

  3. C

    A, B and D only

  4. D

    A and C only

Show answer

Correct option: D

Q70JEE Main 2024 Jan 31 Shift 2Coordination CompoundsEasy

Select the option with correct property -

  1. A

    [NiCl4]2āˆ’\mathrm{[NiCl_4]^{2-}} Diamagnetic, [Ni(CO)4]\mathrm{[Ni(CO)_4]} Paramagnetic

  2. B

    [Ni(CO)4]\mathrm{[Ni(CO)_4]} Diamagnetic, [NiCl4]2āˆ’\mathrm{[NiCl_4]^{2-}} Paramagnetic

  3. C

    [Ni(CO)4]\mathrm{[Ni(CO)_4]} and [NiCl4]2āˆ’\mathrm{[NiCl_4]^{2-}} both Diamagnetic

  4. D

    [Ni(CO)4]\mathrm{[Ni(CO)_4]} and [NiCl4]2āˆ’\mathrm{[NiCl_4]^{2-}} both Paramagnetic

Show answer

Correct option: B

Q71JEE Main 2024 Jan 31 Shift 2Coordination CompoundsMedium

Match List I with List II

LIST I (Complex ion) LIST II (Electronic Configuration)
A. [Cr(H2O)6]3+\mathrm{[Cr(H_2O)_6]^{3+}} I. t2g2 eg0t_{2g}^{2}\,e_g^{0}
B. [Fe(H2O)6]3+\mathrm{[Fe(H_2O)_6]^{3+}} II. t2g3 eg0t_{2g}^{3}\,e_g^{0}
C. [Ni(H2O)6]2+\mathrm{[Ni(H_2O)_6]^{2+}} III. t2g3 eg2t_{2g}^{3}\,e_g^{2}
D. [V(H2O)6]3+\mathrm{[V(H_2O)_6]^{3+}} IV. t2g6 eg2t_{2g}^{6}\,e_g^{2}

Choose the correct answer from the options given below:

  1. A

    A-II, B-III, C-IV, D-I

  2. B

    A-III, B-II, C-IV, D-I

  3. C

    A-IV, B-I, C-II, D-III

  4. D

    A-IV, B-III, C-I, D-II

Show answer

Correct option: A

Q72JEE Main 2024 Jan 31 Shift 2Purification and Characterisation of Organic CompoundsEasy

The fragrance of flowers is due to the presence of some steam volatile organic compounds called essential oils. These are generally insoluble in water at room temperature but are miscible with water vapour in vapour phase. A suitable method for the extraction of these oils from the flowers is -

  1. A

    distillation

  2. B

    crystallisation

  3. C

    distillation under reduced pressure

  4. D

    steam distillation

Show answer

Correct option: D

Q73JEE Main 2024 Jan 31 Shift 2HydrocarbonsEasy

The correct order of reactivity in electrophilic substitution reaction of the following compounds is :

[Figure: four benzene-ring structures — A: benzene, B: toluene (C6H5CH3\mathrm{C_6H_5CH_3}), C: chlorobenzene (C6H5Cl\mathrm{C_6H_5Cl}), D: nitrobenzene (C6H5NO2\mathrm{C_6H_5NO_2})]

  1. A

    A > B > C > D

  2. B

    D > C > B > A

  3. C

    B > C > A > D

  4. D

    B > A > C > D

Show answer

Correct option: D

Q74JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing HalogensEasy

Identify structure of 2,3–dibromo–1–phenylpentane.

  1. A

    [Figure: skeletal structure] C6H5āˆ’CH2āˆ’CH2āˆ’CH(Br)āˆ’CH(Br)āˆ’CH3\mathrm{C_6H_5-CH_2-CH_2-CH(Br)-CH(Br)-CH_3}

  2. B

    [Figure: skeletal structure] C6H5āˆ’CH(Br)āˆ’CH(Br)āˆ’CH2āˆ’CH2āˆ’CH3\mathrm{C_6H_5-CH(Br)-CH(Br)-CH_2-CH_2-CH_3}

  3. C

    [Figure: skeletal structure] C6H5āˆ’CH2āˆ’CH(Br)āˆ’CH(Br)āˆ’CH2āˆ’CH3\mathrm{C_6H_5-CH_2-CH(Br)-CH(Br)-CH_2-CH_3}

  4. D

    [Figure: skeletal structure] C6H5āˆ’CH(Br)āˆ’CH2āˆ’CH(Br)āˆ’CH2āˆ’CH3\mathrm{C_6H_5-CH(Br)-CH_2-CH(Br)-CH_2-CH_3}

Show answer

Correct option: C

Q75JEE Main 2024 Jan 31 Shift 2HydrocarbonsMedium

Major product of the following reaction is -

[Figure: 1-methylcyclopent-1-ene treated with Dāˆ’Cl\mathrm{D-Cl}]

1-methylcyclopentene→Dāˆ’Cl?\text{1-methylcyclopentene} \xrightarrow{\mathrm{D-Cl}} ?

  1. A

    [Figure: cyclopentane ring with adjacent carbons — one bearing D (up) and H (down), the other bearing CH3\mathrm{CH_3} (up) and Cl (down); i.e. Cl and CH3\mathrm{CH_3} on the same carbon, with D and CH3\mathrm{CH_3} cis]

  2. B

    [Figure: cyclopentane ring with adjacent carbons — one bearing D (up) and H (down), the other bearing Cl (up) and CH3\mathrm{CH_3} (down); i.e. Cl and CH3\mathrm{CH_3} on the same carbon, with D and Cl cis]

  3. C

    [Figure: cyclopentane ring with adjacent carbons — one bearing H (up) and Cl (down), the other bearing D (up) and CH3\mathrm{CH_3} (down); i.e. D and CH3\mathrm{CH_3} on the same carbon, with Cl on the adjacent carbon]

  4. D

    [Figure: cyclopentane ring with adjacent carbons — one bearing Cl (up) and H (down), the other bearing D (up) and CH3\mathrm{CH_3} (down); i.e. D and CH3\mathrm{CH_3} on the same carbon, with Cl cis to D on the adjacent carbon]

Show answer

Correct option: A

Q76JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing HalogensMedium

Identify A and B in the following reaction sequence.

Bromobenzene→ConcĀ HNO3A→(ii)Ā HCl(i)Ā NaOHB\text{Bromobenzene} \xrightarrow{\text{Conc } \mathrm{HNO_3}} \mathrm{A} \xrightarrow[\text{(ii) } \mathrm{HCl}]{\text{(i) } \mathrm{NaOH}} \mathrm{B}

[Figure: reaction scheme starting from bromobenzene]

  1. A

    [Figure] A = 1-bromo-4-nitrobenzene; B = benzene ring with Br, OH ortho to Br and NO2\mathrm{NO_2} para to Br (2-bromo-4-nitrophenol skeleton)

  2. B

    [Figure] A = 1-bromo-2,4-dinitrobenzene; B = benzene ring with Br, OH ortho to Br and OH para to Br

  3. C

    [Figure] A = 2,4,6-trinitrobromobenzene (Br with NO2\mathrm{NO_2} at both ortho and para positions); B = 2,4,6-trinitrophenol (OH with NO2\mathrm{NO_2} at both ortho and para positions)

  4. D

    [Figure] A = nitrobenzene; B = 3-nitrophenol (NO2\mathrm{NO_2} meta to OH)

Show answer

Correct option: C

Q77JEE Main 2024 Jan 31 Shift 2HydrocarbonsEasy

Identify major product 'P' formed in the following reaction.

C6H6+C6H5COCl→AnhydrousĀ AlCl3’P’ (MajorĀ Product)\mathrm{C_6H_6} + \mathrm{C_6H_5COCl} \xrightarrow{\text{Anhydrous } \mathrm{AlCl_3}} \text{'P' (Major Product)}

[Figure: benzene plus benzoyl chloride reaction scheme]

  1. A

    [Figure] Benzaldehyde, C6H5CHO\mathrm{C_6H_5CHO}

  2. B

    [Figure] Benzophenone, C6H5COC6H5\mathrm{C_6H_5COC_6H_5}

  3. C

    [Figure] Phenoxy-substituted benzoyl chloride, C6H5āˆ’Oāˆ’C6H4āˆ’COCl\mathrm{C_6H_5-O-C_6H_4-COCl}

  4. D

    [Figure] Acetophenone, C6H5COCH3\mathrm{C_6H_5COCH_3}

Show answer

Correct option: B

Q78JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing OxygenEasy

Identify the name reaction.

C6H6→Anhyd.Ā AlCl3/CuClCO,Ā HClC6H5CHO\mathrm{C_6H_6} \xrightarrow[\text{Anhyd. } \mathrm{AlCl_3/CuCl}]{\mathrm{CO,\ HCl}} \mathrm{C_6H_5CHO}

  1. A

    Etard Reaction

  2. B

    Stephen Reaction

  3. C

    Gatterman - Koch Reaction

  4. D

    Rosenmund Reduction

Show answer

Correct option: C

Q79JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing NitrogenMedium

Given below are two statements :

Statement I : Aniline reacts with con. H2SO4\mathrm{H_2SO_4}, followed by heating at 453 - 473 K gives p-aminobenzene sulphonic acid, which gives blood red colour in the 'Lassaigne's test'.

Statement II : In Friedel - Craft's alkylation and acylation reactions, aniline forms salt with the AlCl3\mathrm{AlCl_3} catalyst. Due to this, nitrogen of aniline aquires a positive charge and acts as deactivating group.

In the light of the above statements, choose the correct answer from the options given below :

  1. A

    Both statement I and statement II are true

  2. B

    Both statement I and statement II are false

  3. C

    Statement I is true but statement II is false

  4. D

    Statement I is false but statement II is true

Show answer

Correct option: A

Q80JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing NitrogenMedium

The azo-dye (YY) formed in the following reactions is

Sulphanilic acid + NaNO2\mathrm{NaNO_2} + CH3COOH\mathrm{CH_3COOH} → X.

X+naphthalen-1-amine⟶Y\mathrm{X} + \text{naphthalen-1-amine} \longrightarrow \mathrm{Y}

[Figure: X reacting with 1-aminonaphthalene (naphthalene with NH2\mathrm{NH_2} at position 1)]

  1. A

    [Figure] HSO3āˆ’C6H4āˆ’N=Nāˆ’\mathrm{HSO_3-C_6H_4-N{=}N-}naphthalene with NH2\mathrm{NH_2} on the same ring as the azo linkage (azo group and NH2\mathrm{NH_2} both on the top ring, at positions 1 and 4)

  2. B

    [Figure] HSO3āˆ’C6H4āˆ’N=Nāˆ’\mathrm{HSO_3-C_6H_4-N{=}N-}naphthalene with NH2\mathrm{NH_2} on the other ring (azo group at position 1, NH2\mathrm{NH_2} at position 5)

  3. C

    [Figure] Bis-azo structure: two HO3S\mathrm{HO_3S}-bearing naphthalene units each linked through N=N\mathrm{N{=}N}, one unit carrying NH2\mathrm{NH_2}

  4. D

    [Figure] HSO3āˆ’C6H4āˆ’N=Nāˆ’\mathrm{HSO_3-C_6H_4-N{=}N-}naphthaleneāˆ’N=Nāˆ’C6H4āˆ’SO3H\mathrm{-N{=}N-C_6H_4-SO_3H} (naphthalene bearing two azo linkages, one on each ring)

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Correct option: A

Q81JEE Main 2024 Jan 31 Shift 2Chemical Bonding and Molecular StructureMediumNumerical

A diatomic molecule has a dipole moment of 1.2 D. If the bond distance is 1Ā A˚1\ \mathrm{\AA}, then fractional charge on each atom is _______ Ɨ10āˆ’1\times 10^{-1} esu.

(Given 1 D = 10āˆ’1810^{-18} esucm)

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Answer: 0

Q82JEE Main 2024 Jan 31 Shift 2Chemical ThermodynamicsMediumNumerical

If 5 moles of an ideal gas expands from 10 L to a volume of 100 L at 300 K under isothermal and reversible condition then work, w, is āˆ’x-x J. The value of xx is _________.

(Given R=8.314Ā JĀ Kāˆ’1Ā molāˆ’1\mathrm{R} = 8.314\ \mathrm{J\ K^{-1}\ mol^{-1}})

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Answer: 28721

Q83JEE Main 2024 Jan 31 Shift 2Some Basic Concepts in ChemistryMediumNumerical

The molarity of 1 L orthophosphoric acid (H3PO4\mathrm{H_3PO_4}) having 70% purity by weight (specific gravity 1.54Ā gĀ cmāˆ’31.54\ \mathrm{g\ cm^{-3}}) is ________ M.

(Molar mass of H3PO4\mathrm{H_3PO_4} = 98Ā gĀ molāˆ’198\ \mathrm{g\ mol^{-1}})

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Answer: 11

Q84JEE Main 2024 Jan 31 Shift 2Redox Reactions and ElectrochemistryEasyNumerical

The values of conductivity of some materials at 298.15 K in SĀ māˆ’1\mathrm{S\ m^{-1}} are 2.1Ɨ1032.1 \times 10^{3}, 1.0Ɨ10āˆ’161.0 \times 10^{-16}, 1.2Ɨ101.2 \times 10, 3.913.91, 1.5Ɨ10āˆ’21.5 \times 10^{-2}, 1Ɨ10āˆ’71 \times 10^{-7}, 1.0Ɨ1031.0 \times 10^{3}. The number of conductors among the materials is ________.

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Answer: 4

Q85JEE Main 2024 Jan 31 Shift 2Chemical KineticsMediumNumerical

r=k [A]r = k\,[\mathrm{A}] for a reaction, 50% of A is decomposed in 120 minutes. The time taken for 90% decomposition of A is ________ minutes.

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Answer: 399

Q86JEE Main 2024 Jan 31 Shift 2Redox Reactions and ElectrochemistryMediumNumerical

Number of moles of H+\mathrm{H^+} ions required by 1 mole of MnO4āˆ’\mathrm{MnO_4^-} to oxidise oxalate ion to CO2\mathrm{CO_2} is _______.

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Answer: 4

Q87JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing HalogensMediumNumerical

Number of isomeric products formed by monochlorination of 2-methylbutane in presence of sunlight is ________.

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Answer: 6

Q88JEE Main 2024 Jan 31 Shift 2Organic Compounds Containing NitrogenMediumNumerical

A compound (xx) with molar mass 108Ā gĀ molāˆ’1108\ \mathrm{g\ mol^{-1}} undergoes acetylation to give product with molar mass 192Ā gĀ molāˆ’1192\ \mathrm{g\ mol^{-1}}. The number of amino groups in the compund (xx) is _______.

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Answer: 2

Q89JEE Main 2024 Jan 31 Shift 2BiomoleculesEasyNumerical

From the vitamins A, B1\mathrm{B_1}, B6\mathrm{B_6}, B12\mathrm{B_{12}}, C, D, E and K, the number of vitamins that can be stored in our body is________.

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Answer: 5

Q90JEE Main 2024 Jan 31 Shift 2d- and f-Block ElementsMediumNumerical

In the reaction of potassium dichromate, potassium chloride and sulfuric acid (conc.), the oxidation state of the chromium in the product is (+)________.

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Answer: 6