JEE Main 2024 · previous year paper

JEE Main 2024 — 4 April, Shift 1

81 questions with the verified answer key. Open any question for its step-by-step solution.

  1. Question 1Mathematics· Limits, Continuity and Differentiability

    Let f:R→Rf: \mathbf{R} \rightarrow \mathbf{R} be a function given by f(x)={1−cos⁡2xx2,x<0,α,x=0,β1−cos⁡xx,x>0.f(x)=\begin{cases}\frac{1-\cos 2x}{x^2}, & x<0,\\\alpha, & x=0,\\\frac{\beta\sqrt{1-\cos x}}{x}, & x>0.\end{cases} where β∈R\beta \in \mathrm{R} f is continues at x=0\mathrm{x}=0 , then α2+β2 \alpha^2+\beta^2 is equal to :

    1. Option A:

      48

    2. Option B:

      12

    3. Option C:

      3

    4. Option D:

      6

  2. Question 2Mathematics· Probability

    Three urns A, B and C contain 7 red, 5 black; 5 red, 7 black and 6 red, 6 black balls, respectively. One of the urn is selected at random and a ball is drawn from it. If the ball drawn is black, then the probability that it is drawn from urn A is :

    1. Option A:

      417\frac{4}{17}

    2. Option B:

      518\frac{5}{18}

    3. Option C:

      718\frac{7}{18}

    4. Option D:

      516\frac{5}{16}

  3. Question 3Mathematics· Straight lines

    The vertices of a triangle are A(−1,3),B(−2,2)\mathrm{A}(-1,3), \mathrm{B}(-2,2) and C(3,−1)\mathrm{C}(3,-1). A new triangle is formed by shifting the sides of the triangle by one unit inwards. Then the equation of the side of the new triangle nearest to origin is :

    1. Option A:

      x−y−(2+2)=0x-y-(2+\sqrt{2})=0

    2. Option B:

      −x+y−(2−2)=0-x+y-(2-\sqrt{2})=0

    3. Option C:

      x+y−(2−2)=0x+y-(2-\sqrt{2})=0

    4. Option D:

      x+y+(2−2)=0x+y+(2-\sqrt{2})=0

  4. Question 4Mathematics· Differential Equations

    If the solution y=y(x)y=y(x) of the differential equation (x4+2x3+3x2+2x+2)dy−(2x2+2x+3)dx=0\left(x^{4}+2 x^{3}+3 x^{2}+2 x+2\right) d y-\left(2 x^{2}+2 x+3\right) d x=0 satisfies y(−1)=−π4y(-1)=-\frac{\pi}{4}, then y(0)y(0) is equal to :

    1. Option A:

      −π12-\frac{\pi}{12}

    2. Option B:

      00

    3. Option C:

      π4\frac{\pi}{4}

    4. Option D:

      π2\frac{\pi}{2}

  5. Question 5Mathematics· Functions

    Let the sum of the maximum and the minimum values of the function f(x)=2x2−3x+82x2+3x+8f(x)=\frac{2 x^{2}-3 x+8}{2 x^{2}+3 x+8} be mn\frac{m}{n}, where gcd⁡(m,n)=1\operatorname{gcd}(m, n)=1. Then m+nm+n is equal to:

    1. Option A:

      182

    2. Option B:

      217

    3. Option C:

      195

    4. Option D:

      201

  6. Question 6Mathematics· Area under the Curves

    One of the points of intersection of the curves y=1+3x−2x2y=1+3 x-2 x^{2} and y=1xy=\frac{1}{x} is (12,2)\left(\frac{1}{2}, 2\right).

    Let the area of the region enclosed by these curves be 124(ℓ5+m)−nlog⁡e(1+5)\frac{1}{24}(\ell \sqrt{5}+\mathrm{m})-\mathrm{n} \log _{\mathrm{e}}(1+\sqrt{5}), where ℓ,m,n∈\ell, \mathrm{m}, \mathrm{n} \in N .

    Then ℓ+m+n\ell+\mathrm{m}+\mathrm{n} is equal to

    1. Option A:

      32

    2. Option B:

      30

    3. Option C:

      29

    4. Option D:

      31

  7. Question 7Mathematics· Determinants

    If the system of equations

    x+(2sin⁡α)y+(2cos⁡α)z=0x+(\sqrt{2} \sin \alpha) y+(\sqrt{2} \cos \alpha) z=0,x+(cos⁡α)y+(sin⁡α)z=0x+(\cos \alpha) y+(\sin \alpha) z=0,x+(sin⁡α)y−(cos⁡α)z=0x+(\sin \alpha) y-(\cos \alpha) z=0

    has a non-trivial solution, then α∈(0,π2)\alpha \in\left(0, \frac{\pi}{2}\right) is equal to :

    1. Option A:

      3π4\frac{3 \pi}{4}

    2. Option B:

      7π24\frac{7 \pi}{24}

    3. Option C:

      5π24\frac{5 \pi}{24}

    4. Option D:

      11π24\frac{11 \pi}{24}

  8. Question 8Mathematics· Permutations and Combinations

    There are 5 points P1,P2,P3,P4,P5\mathrm{P}_{1}, \mathrm{P}_{2}, \mathrm{P}_{3}, \mathrm{P}_{4}, \mathrm{P}_{5} on the side AB , excluding A and B , of a triangle ABC . Similarly there are 6 points P6,P7,…,P11\mathrm{P}_{6}, \mathrm{P}_{7}, \ldots, \mathrm{P}_{11} on the side BC and 7 points P12,P13,…,P18\mathrm{P}_{12}, \mathrm{P}_{13}, \ldots, \mathrm{P}_{18} on the side CA of the triangle. The number of triangles, that can be formed using the points P1,P2,…,P18\mathrm{P}_{1}, \mathrm{P}_{2}, \ldots, \mathrm{P}_{18} as vertices, is :

    1. Option A:

      776

    2. Option B:

      751

    3. Option C:

      796

    4. Option D:

      771

  9. Question 9Mathematics· Definite Integration

    Let f(x)={−2,−2≤x≤0x−2,0<x≤2f\left( \text{x} \right)=\left\{ \begin{matrix}-2, & -2\le \text{x}\le 0 \\\text{x}-2, & 0<\text{x}\le 2 \\\end{matrix} \right. and h(x)=f(∣x∣)+∣f(x)∣\text{h}\left( \text{x} \right)=\text{f}\left(\left| \text{x}\right| \right)+\left| \text{f}\left( \text{x} \right) \right|.Then ∫−22  ⁣ ⁣  ⁣ ⁣ h(x)dx\int _{-2}^{2}\text{ }\!\!~\!\!\text{ h}\left( \text{x} \right)\text{dx} is equal to :

    1. Option A:

      2

    2. Option B:

      4

    3. Option C:

      1

    4. Option D:

      6

  10. Question 10Mathematics· Binomial Theorem

    The sum of all rational terms in the expansion of (215+513)15\left(2^\frac{1}{5}+5^\frac{1}{3}\right)^{15}\\ is equal to:

    1. Option A:

      3133

    2. Option B:

      633

    3. Option C:

      931

    4. Option D:

      6131

  11. Question 11Mathematics· Vector Algebra

    Let a unit vector which makes an angle of 60∘60^{\circ} with 2i^+2j^−k^2 \hat{i}+2 \hat{j}-\hat{k} and an angle of 45∘45^{\circ} with i^−k^\hat{i}-\hat{k} be C⃗\vec{C}. Then C→+(−12i^+132j^−23k^)\overrightarrow{\mathrm{C}}+\left(-\frac{1}{2} \hat{\mathrm{i}}+\frac{1}{3 \sqrt{2}} \hat{\mathrm{j}}-\frac{\sqrt{2}}{3} \hat{\mathrm{k}}\right) is :

    1. Option A:

      −23i^+23j^+(12+223)k^-\frac{\sqrt{2}}{3} \hat{\mathrm{i}}+\frac{\sqrt{2}}{3} \hat{\mathrm{j}}+\left(\frac{1}{2}+\frac{2 \sqrt{2}}{3}\right) \hat{\mathrm{k}}

    2. Option B:

      23i^+132j^−12k^\frac{\sqrt{2}}{3} \hat{i}+\frac{1}{3 \sqrt{2}} \hat{j}-\frac{1}{2} \hat{k}

    3. Option C:

      (13+12)i^+(13−132)j^+(13+23)k^\left(\frac{1}{\sqrt{3}}+\frac{1}{2}\right) \hat{\mathrm{i}}+\left(\frac{1}{\sqrt{3}}-\frac{1}{3 \sqrt{2}}\right) \hat{\mathrm{j}}+\left(\frac{1}{\sqrt{3}}+\frac{\sqrt{2}}{3}\right) \hat{\mathrm{k}}

    4. Option D:

      23i^−12k^\frac{\sqrt{2}}{3} \hat{i}-\frac{1}{2} \hat{k}

  12. Question 12Mathematics· Sequence and Series

    Let the first three terms 2,p2, p and qq, with q≠2q \neq 2, of a G.P. be respectively the 7th ,8th 7^{\text {th }}, 8^{\text {th }} and 13th 13^{\text {th }} terms of an A.P. If the 5th 5^{\text {th }} term of the G.P. is the nth \mathrm{n}^{\text {th }} term of the A.P., then nn is equal to

    1. Option A:

      151

    2. Option B:

      169

    3. Option C:

      177

    4. Option D:

      163

  13. Question 13Mathematics· Statistics

    Let a,b∈Ra, b \in R. Let the mean and the variance of 6 observations −3,4,7,−6,a,b-3,4,7,-6, \mathrm{a}, \mathrm{b} be 2 and 23 , respectively. The mean deviation about the mean of these 6 observations is :

    1. Option A:

      133\frac{13}{3}

    2. Option B:

      163\frac{16}{3}

    3. Option C:

      113\frac{11}{3}

    4. Option D:

      143\frac{14}{3}

  14. Question 14Mathematics· Quadratic Equations

    If 2 and 6 are the roots of the equation ax2+bx+1=0a x^{2}+b x+1=0, then the quadratic equation, whose roots are 12a+b\frac{1}{2 a+b} and 16a+b\frac{1}{6 a+b}, is :

    1. Option A:

      2x2+11x+12=02 x^{2}+11 x+12=0

    2. Option B:

      4x2+14x+12=04 x^{2}+14 x+12=0

    3. Option C:

      x2+10x+16=0x^{2}+10 x+16=0

    4. Option D:

      x2+8x+12=0x^{2}+8 x+12=0

  15. Question 15Mathematics· Complex Numbers

    Let α\alpha and β\beta be the sum and the product of all the non-zero solutions of the equation (zˉ)2+∣z∣=0,z∈C(\bar{z})^{2}+|z|=0, z \in C. Then 4(α2+β2)4\left(\alpha^{2}+\beta^{2}\right) is equal to :

    1. Option A:

      6

    2. Option B:

      4

    3. Option C:

      8

    4. Option D:

      2

  16. Question 16Mathematics· 3D Geometry

    Let the point, on the line passing through the points P(1,−2,3)\mathrm{P}(1,-2,3) and Q(5,−4,7)\mathrm{Q}(5,-4,7), farther from the origin and at a distance of 9 units from the point PP, be (α,β,γ)(\alpha, \beta, \gamma). Then α2+β2+γ2\alpha^{2}+\beta^{2}+\gamma^{2} is equal to :

    1. Option A:

      155

    2. Option B:

      3

    3. Option C:

      160

    4. Option D:

      165

  17. Question 17Mathematics· Circles

    A square is inscribed in the circle x2+y2−10x−6y+30=0x^{2}+y^{2}-10 x-6 y+30=0. One side of this square is parallel to y=x+3y=x+3.

    If (xi,yi)\left(x_{i}, y_{i}\right) are the vertices of the square, then ∑(xi2+yi2)\sum\left(x_{i}^{2}+y_{i}^{2}\right) is equal to :

    1. Option A:

      148

    2. Option B:

      156

    3. Option C:

      160

    4. Option D:

      152

  18. Question 18Mathematics· Functions

    If the domain of the function sin⁡−1(3x−222x−19)+log⁡e(3x2−8x+5x2−3x−10)\sin ^{-1}\left(\frac{3 x-22}{2 x-19}\right)+\log _{e}\left(\frac{3 x^{2}-8 x+5}{x^{2}-3 x-10}\right) is (α,β](\alpha, \beta], then 3α+10β3 \alpha+10 \beta is equal to :

    1. Option A:

      97

    2. Option B:

      100

    3. Option C:

      95

    4. Option D:

      98

  19. Question 19Mathematics· Methods of Differentiation

    Let f(x)=x5+2ex/4f(\mathrm{x})=\mathrm{x}^{5}+2 \mathrm{e}^{\mathrm{x} / 4} for all x∈\mathrm{x} \in R. Consider a function g(x)g(x) such that (gof) (x)=x(x)=x for all x∈Rx \in R. Then the value of 8 g′(2)8 \mathrm{~g}^{\prime}(2) is :

    1. Option A:

      16

    2. Option B:

      4

    3. Option C:

      8

    4. Option D:

      2

  20. Question 20Mathematics· Matrices

    Let \text{A}=\left[ \begin{array}{*{35}{l}}1 & 2 & \alpha \\1 & 0 & 1 \\0 & 1 & 2 \\\end{array} \right].If det⁡(adj⁡(2 A−AT)⋅adj⁡(A−2 AT))=28\operatorname{det}\left(\operatorname{adj}\left(2 \mathrm{~A}-\mathrm{A}^{\mathrm{T}}\right) \cdot \operatorname{adj}\left(\mathrm{A}-2 \mathrm{~A}^{\mathrm{T}}\right)\right)=2^{8}, then (det⁡(A))2(\operatorname{det}(\mathrm{A}))^{2} is equal to :

    1. Option A:

      1

    2. Option B:

      49

    3. Option C:

      16

    4. Option D:

      36

  21. Question 21Mathematics· Limits, Continuity and Differentiability

    If lim⁡x→1(5x+1)1/3−(x+5)1/3(2x+3)1/2−(x+4)1/2=m5n(2n)2/3\lim _{x \rightarrow 1} \frac{(5 x+1)^{1 / 3}-(x+5)^{1 / 3}}{(2 x+3)^{1 / 2}-(x+4)^{1 / 2}}=\frac{m \sqrt{5}}{n(2 n)^{2 / 3}}, where gcd⁡(m,n)=1\operatorname{gcd}(\mathrm{m}, \mathrm{n})=1, then 8 m+12n8 \mathrm{~m}+12 \mathrm{n} is equal to \qquad

  22. Question 22Mathematics· Sets and Relations

    In a survey of 220 students of a higher secondary school, it was found that at least 125 and at most 130 students studied Mathematics; at least 85 and at most 95 studied Physics; at least 75 and at most 90 studied Chemistry; 30 studied both Physics and Chemistry; 50 studied both Chemistry and Mathematics; 40 studied both Mathematics and Physics and 10 studied none of these subjects. Let m and n respectively be the least and the most number of students who studied all the three subjects. Then m+n\mathrm{m}+\mathrm{n} is equal to \qquad

  23. Question 23Mathematics· Differential Equations

    Let the solution y=y(x)\mathrm{y}=\mathrm{y}(\mathrm{x}) of the differential equation dydx−y=1+4sin⁡x\frac{d y}{d x}-y=1+4 \sin x satisfy y(π)=1y(\pi)=1. Then y(π2)+10\mathrm{y}\left(\frac{\pi}{2}\right)+10 is equal to \qquad

  24. Question 24Mathematics· 3D Geometry

    If the shortest distance between the lines x+22=y+33=z−54\frac{x+2}{2}=\frac{y+3}{3}=\frac{z-5}{4} and x−31=y−2−3=z+42\frac{x-3}{1}=\frac{y-2}{-3}=\frac{z+4}{2} is 3835k\frac{38}{3 \sqrt{5}} \mathrm{k} \quad

    and ∫0k[x2]dx=α−α,\quad \int_{0}^{\mathrm{k}}\left[\mathrm{x}^{2}\right] \mathrm{dx}=\alpha-\sqrt{\alpha}, \quad where [x]\quad[\mathrm{x}] denotes the greatest integer function, then 6α36 \alpha^{3} is equal to \qquad

  25. Question 25Mathematics· Hyperbola

    Let A be a square matrix of order 2 such that ∣A∣=2|A|=2 and the sum of its diagonal elements is -3 . If the points (x,y)(x, y) satisfying A2+xA+yI=0A^{2}+x A+y I=0 lie on a hyperbola, whose transverse axis is parallel to the x -axis, eccentricity is e and the length of the latus rectum is ℓ\ell, then e4+ℓ4\mathrm{e}^{4}+\ell^{4} is equal to \qquad

  26. Question 26Mathematics· Binomial Theorem

    Let a=1+ 2C23!+ 3C24!+ 4C25!+…\text{a}=1+\frac{{{~}^{2}}{{\text{C}}_{2}}}{3!}+\frac{{{~}^{3}}{{\text{C}}_{2}}}{4!}+\frac{{{~}^{4}}{{\text{C}}_{2}}}{5!}+\ldots

    b=1+ 1C0+ 1C11!+ 2C0+ 2C1+ 2C22!+ 3C0+ 3C1+ 3C2+ 3C33!+…\text{b}=1+\frac{{{~}^{1}}{{\text{C}}_{0}}+{{~}^{1}}{{\text{C}}_{1}}}{1!}+\frac{{{~}^{2}}{{\text{C}}_{0}}+{{~}^{2}}{{\text{C}}_{1}}+{{~}^{2}}{{\text{C}}_{2}}}{2!}+\frac{{{~}^{3}}{{\text{C}}_{0}}+{{~}^{3}}{{\text{C}}_{1}}+{{~}^{3}}{{\text{C}}_{2}}+{{~}^{3}}{{\text{C}}_{3}}}{3!}+\ldots

    Then 2ba2\frac{2b}{{{a}^{2}}} is equal to   ⁣ ⁣  ⁣ ⁣ \text{ }\!\!~\!\!\text{ }

  27. Question 27Mathematics· Determinants

    Let AA be a 3×33 \times 3 matrix of non-negative real elements such that \text{A}\left[ \begin{array}{*{35}{l}}1 \\1 \\1 \\\end{array} \right]=3\left[ \begin{array}{*{35}{l}}1 \\1 \\1 \\\end{array} \right]. Then the maximum value of det⁡(A)\operatorname{det}(\mathrm{A}) is \qquad

  28. Question 28Mathematics· Parabola

    Let the length of the focal chord PQP Q of the parabola y2=12xy^{2}=12 x be 15 units. If the distance of PQP Q from the origin is pp, then 10p210 p^{2} is equal to \qquad

  29. Question 29Mathematics· Vector Algebra

    Let ABCABC be a triangle of area 15215\sqrt{2}. Let the vectors representing its sides be:

    AB→=i^+2j^−7k^\overrightarrow{AB} = \hat{i} + 2\hat{j} - 7\hat{k} BC→=ai^+bj^+ck^\overrightarrow{BC} = a\hat{i} + b\hat{j} + c\hat{k} AC→=6i^+dj^−2k^(where d>0)\overrightarrow{AC} = 6\hat{i} + d\hat{j} - 2\hat{k} \quad (\text{where } d > 0)

    Then the square of the length of the largest side of the triangle ABCABC is :

  30. Question 30Mathematics· Definite Integration

    If ∫0π4sin⁡2x1+sin⁡xcos⁡xdx=1alog⁡e(a3)+πb3\int_{0}^{\frac{\pi}{4}} \frac{\sin ^{2} x}{1+\sin x \cos x} d x=\frac{1}{a} \log _{e}\left(\frac{a}{3}\right)+\frac{\pi}{b \sqrt{3}}, where aa, b∈N\mathrm{b} \in \mathrm{N}, then a+b\mathrm{a}+\mathrm{b} is equal to \qquad

  31. Question 31Physics· Moving Charges and Magnetic Field

    An electron is projected with uniform velocity along the axis inside a current carrying long solenoid. Then :

    1. Option A:

      the electron will be accelerated along the axis.

    2. Option B:

      the electron will continue to move with uniform velocity along the axis of the solenoid.

    3. Option C:

      the electron path will be circular about the axis.

    4. Option D:

      the electron will experience a force at 45∘45^{\circ} to the axis and execute a helical path.

  32. Question 32Physics· Electromagnetic Waves

    The electric field in an electromagnetic wave is given by E⃗=i^40cos⁡ω(t−zc)NC−1.\vec{E}=\hat{\mathrm{i}} 40 \cos \omega\left(t-\frac{z}{c}\right) N C^{-1} . \quad

    The magnetic field induction of this wave is (in SI unit):

    1. Option A:

      B⃗=i^40ccos⁡ω(t−zc)\vec{B}=\hat{i} \frac{40}{c} \cos \omega\left(t-\frac{z}{c}\right)

    2. Option B:

      B→=j^40cos⁡ω(t−zc)\overrightarrow{\mathrm{B}}=\hat{\mathrm{j}} 40 \cos \omega\left(t-\frac{\mathrm{z}}{\mathrm{c}}\right)

    3. Option C:

      B→=k^40ccos⁡ω(t−zc)\overrightarrow{\mathrm{B}}=\hat{\mathrm{k}} \frac{40}{\mathrm{c}} \cos \omega\left(\mathrm{t}-\frac{\mathrm{z}}{\mathrm{c}}\right)

    4. Option D:

      B⃗=j^40ccos⁡ω(t−zc)\vec{B}=\hat{j} \frac{40}{c} \cos \omega\left(t-\frac{z}{c}\right)

  33. Question 33Physics· Nuclear Physics

    Which of the following nuclear fragments corresponding to nuclear fission between neutron (01n)\left({ }_{0}^{1} \mathrm{n}\right) and uranium isotope (92235U)\left({ }_{92}^{235} \mathrm{U}\right) is correct:

    1. Option A:

      56144Ba+3689Kr+401n{ }_{56}^{144} \mathrm{Ba}+{ }_{36}^{89} \mathrm{Kr}+4_{0}^{1} \mathrm{n}

    2. Option B:

      56140Xe+3894Sr+301n{ }_{56}^{140} \mathrm{Xe}+{ }_{38}^{94} \mathrm{Sr}+3{ }_{0}^{1} \mathrm{n}

    3. Option C:

      51153Sb+4199Nb+301n{ }_{51}^{153} \mathrm{Sb}+{ }_{41}^{99} \mathrm{Nb}+3{ }_{0}^{1} \mathrm{n}

    4. Option D:

      56144Ba+3689Kr+301n{ }_{56}^{144} \mathrm{Ba}+{ }_{36}^{89} \mathrm{Kr}+3{ }_{0}^{1} \mathrm{n}

  34. Question 34Physics· Units, Dimensions & Error Analysis

    In an experiment to measure focal length (f) of convex lens, the least counts of the measuring scales for the position of object ( uu ) and for the position of image ( vv ) are Δu\Delta u and Δv\Delta v, respectively. The error in the measurement of the focal length of the convex lens will be :

    1. Option A:

      Δuu+Δvv\frac{\Delta u}{u}+\frac{\Delta v}{v}

    2. Option B:

      f2[Δuu2+Δvv2]\mathrm{f}^{2}\left[\frac{\Delta \mathrm{u}}{\mathrm{u}^{2}}+\frac{\Delta \mathrm{v}}{\mathrm{v}^{2}}\right]

    3. Option C:

      2f[Δuu+Δvv]2 f\left[\frac{\Delta u}{u}+\frac{\Delta v}{v}\right]

    4. Option D:

      f[Δuu+Δvv]f\left[\frac{\Delta \mathrm{u}}{\mathrm{u}}+\frac{\Delta \mathrm{v}}{\mathrm{v}}\right]

  35. Question 35Physics· Fluid Mechanics

    Given below are two statements :

    Statement I : When speed of liquid is zero everywhere, pressure difference at any two points depends on equation P1−P2=ρg( h2−h1)\mathrm{P}_{1}-\mathrm{P}_{2}=\rho g\left(\mathrm{~h}_{2}-\mathrm{h}_{1}\right)

    Statement II : In ventury tube shown, 2gh=v12−v222 \mathrm{gh}=v_{1}^{2}-v_{2}^{2}

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

    Question 35 figure
    1. Option A:

      Both Statement I and Statement II are correct.

    2. Option B:

      Statement I is incorrect but Statement II is correct.

    3. Option C:

      Both Statement I and Statement II are incorrect.

    4. Option D:

      Statement I is correct but Statement II is incorrect.

  36. Question 36Physics· Thermal Properties of Matter

    The resistances of the platinum wire of a platinum resistance thermometer at the ice point and steam point are 8Ω8 \Omega and 10Ω10 \Omega respectively. After inserting in a hot bath of temperature 400∘C400^{\circ} \mathrm{C}, the resistance of platinum wire is :

    1. Option A:

      2Ω2 \Omega

    2. Option B:

      16Ω16 \Omega

    3. Option C:

      8Ω8 \Omega

    4. Option D:

      10Ω10 \Omega

  37. Question 37Physics· Gravitation

    A metal wire of uniform mass density having length LL and mass MM is bent to form a semicircular arc and a particle of mass mm is placed at the centre of the arc. The gravitational force on the particle by the wire is:

    1. Option A:

      GMmπ2 L2\frac{\mathrm{GMm} \pi}{2 \mathrm{~L}^{2}}

    2. Option B:

      zero

    3. Option C:

      GmMπ2L2\frac{G m M \pi^{2}}{L^{2}}

    4. Option D:

      2GmMπL2\frac{2 \mathrm{GmM} \pi}{\mathrm{L}^{2}}

  38. Question 38Physics· Thermal Properties of Matter

    On celcius scale the temperature of body increases by 40∘C40^{\circ} \mathrm{C}. The increase in temperature on Fahrenheit scale is:

    1. Option A:

      70∘F70^{\circ} \mathrm{F}

    2. Option B:

      68∘F68^{\circ} \mathrm{F}

    3. Option C:

      72∘F72^{\circ} \mathrm{F}

    4. Option D:

      75∘F75^{\circ} \mathrm{F}

  39. Question 39Physics· Geometrical Optics

    An effective power of a combination of 5 identical convex lenses which are kept in contact along the principal axis is 25 D. Focal length of each of the convex lens is :

    1. Option A:

      20 cm

    2. Option B:

      50 cm

    3. Option C:

      500 cm

    4. Option D:

      25 cm

  40. Question 40Physics· Motion in one Dimension

    A wooden block, initially at rest on the ground, is pushed by a force which increases linearly with time tt. Which of the following curve best describes acceleration of the block with time :

    1. Option A:
      Option A figure
    2. Option B:
      Option B figure
    3. Option C:
      Option C figure
    4. Option D:
      Option D figure
  41. Question 41Physics· System Of Particles

    If a rubber ball falls from a height hh and rebounds upto the height of h/2h / 2. The percentage loss of total energy of the initial system as well as velocity ball before it strikes the ground, respectively, are :

    1. Option A:

      50%,gh250 \%, \sqrt{\frac{\mathrm{gh}}{2}}

    2. Option B:

      50%, gh 50 \%, \sqrt{\text { gh }}

    3. Option C:

      40%,2gh40 \%, \sqrt{2 \mathrm{gh}}

    4. Option D:

      50%,2gh50 \%, \sqrt{2 \mathrm{gh}}

  42. Question 42Physics· Units, Dimensions & Error Analysis

    The equation of stationary wave is : y=2asin⁡(2πntλ)cos⁡(2πxλ)y=2 a \sin \left(\frac{2 \pi n t}{\lambda}\right) \cos \left(\frac{2 \pi x}{\lambda}\right). Which of the following is NOT correct?

    1. Option A:

      The dimensions of nt is [L]

    2. Option B:

      The dimensions of n is [LT−1]\left[\mathrm{LT}^{-1}\right]

    3. Option C:

      The dimensions of n/λn / \lambda is [T]

    4. Option D:

      The dimensions of xx is [L]

  43. Question 43Physics· Motion in one Dimension

    A body travels 102.5 m  in   nth 102.5 \mathrm{~m}\; {\text {in }}\; \mathrm{n}^{\text {th }} second and 115.0 m in (n+2)th(\mathrm{n}+2)^{\mathrm{th}} second. The acceleration is :

    1. Option A:

      9 m/s29 \mathrm{~m} / \mathrm{s}^{2}

    2. Option B:

      6.25 m/s26.25 \mathrm{~m} / \mathrm{s}^{2}

    3. Option C:

      12.5 m/s212.5 \mathrm{~m} / \mathrm{s}^{2}

    4. Option D:

      5 m/s25 \mathrm{~m} / \mathrm{s}^{2}

  44. Question 44Physics· Current Electricity

    To measure the internal resistance of a battery, potentiometer is used. For R=10Ω\mathrm{R}=10 \Omega, the balance point is observed at ℓ=500 cm\ell=500 \mathrm{~cm} and for R=1Ω\mathrm{R}=1 \Omega the balance point is observed at ℓ=400 cm\ell=400 \mathrm{~cm}. The internal resistance of the battery is approximately:

    1. Option A:

      0.2Ω0.2 \Omega

    2. Option B:

      0.4Ω0.4 \Omega

    3. Option C:

      0.1Ω0.1 \Omega

    4. Option D:

      0.3Ω0.3 \Omega

  45. Question 45Physics· Electrostatics

    An infinitely long positively charged straight thread has a linear charge density λCm−1\lambda \mathrm{Cm}^{-1}. An electron revolves along a circular path having axis along the length of the wire. The graph that correctly represents the variation of the kinetic energy of electron as a function of radius of circular path from the wire is :

    1. Option A:
      Option A figure
    2. Option B:
      Option B figure
    3. Option C:
      Option C figure
    4. Option D:
      Option D figure
  46. Question 46Physics· Semiconductor and Electronic Devices

    The value of net resistance of the network as shown in the given figure is :

    Question 46 figure
    1. Option A:

      (52)Ω\left(\frac{5}{2}\right) \Omega

    2. Option B:

      (154)Ω\left(\frac{15}{4}\right) \Omega

    3. Option C:

      6Ω6 \Omega

    4. Option D:

      (3011)Ω\left(\frac{30}{11}\right) \Omega

  47. Question 47Physics· Motion in Plane

    The co-ordinates of a particle moving in x−yx-y plane are given by : x=2+4t,y=3t+8t2x=2+4 t, y=3 t+8 t^{2}

    The motion of the particle is :

    1. Option A:

      non-uniformly accelerated.

    2. Option B:

      uniformly accelerated having motion along a straight line.

    3. Option C:

      uniform motion along a straight line.

    4. Option D:

      uniformly accelerated having motion along a parabolic path.

  48. Question 48Physics· Alternating Current

    In an ac circuit, the instantaneous current is zero, when the instantaneous voltage is maximum. In this case, the source may be connected to :

    A. pure inductor.

    B. pure capacitor.

    C. pure resistor.

    D. combination of an inductor and capacitor.

    Choose the correct answer from the options given below:

    1. Option A:

      A, B and C only

    2. Option B:

      B, C and D only

    3. Option C:

      A and B only

    4. Option D:

      A, B and D only

  49. Question 49Physics· Electrostatics

    An infinite plane sheet of charge having uniform surface charge density +σsC/m2+\sigma_{\mathrm{s}} \mathrm{C} / \mathrm{m}^{2} is placed on x−y\mathrm{x}-\mathrm{y} plane. Another infinitely long line charge having uniform linear charge density +λeC/m+\lambda_{\mathrm{e}} \mathrm{C} / \mathrm{m} is placed at z=4 m\mathrm{z}=4 \mathrm{~m} plane and parallel to y -axis. If the magnitude values ∣σs∣=2∣λe∣\left|\sigma_{s}\right|=2\left|\lambda_{e}\right| then at point (0,0,2)(0,0,2), the ratio of magnitudes of electric field values due to sheet charge to that of line charge is πn:1\pi \sqrt{\mathrm{n}}: 1. The value of nn is \qquad .

  50. Question 50Physics· Atomic Physics

    A hydrogen atom changes its state from n=3n=3 to n=2\mathrm{n}=2. Due to recoil, the percentage change in the wave length

    of emitted light is approximately 1×10−n1 \times 10^{-\mathrm{n}}. The value of n is \qquad . [Given Rhc =13.6eV,hc=1242eVnm=13.6 \mathrm{eV}, \mathrm{hc}=1242 \mathrm{eV} \mathrm{nm},

    h=6.6×10−34 J\mathrm{h}=6.6 \times 10^{-34} \mathrm{~J} s, mass of the hydrogen atom =1.6×10−27 kg]\left.=1.6 \times 10^{-27} \mathrm{~kg}\right]

  51. Question 51Physics· Moving Charges and Magnetic Field

    The magnetic field existing in a region is given by B⃗=0.2(1+2x)k^T\vec{B}=0.2(1+2 x) \hat{k} T. A square loop of edge 50 cm carrying 0.5 A current is placed in x−y\mathrm{x}-\mathrm{y} plane with its edges parallel to the x−yx-y axes, as shown in figure. The magnitude of the net magnetic force experienced by the loop is \qquad mN .

    Question 51 figure
  52. Question 52Physics· Alternating Current

    A alternating current at any instant is given by i=[6+56sin⁡(100πt+π3)]\mathrm{i}=\left[6+\sqrt{56} \sin \left(100 \pi \mathrm{t}+\frac{\pi}{3}\right)\right] A. The rms value of the current

    is \qquad A.

  53. Question 53Physics· Current Electricity

    Twelve wires each having resistance 2Ω2 \Omega are joined to form a cube. A battery of 6 V emf is joined across point a and c . The voltage difference between ee and ff is \qquad V.

    Question 53 figure
  54. Question 54Physics· Mechanical Properties of Matter

    A soap bubble is blown to a diameter of 7 cm . 36960 erg of work is done in blowing it further. If surface tension of soap solution is 40 dyne/cm then the new radius is \qquad cm. Take :(π=227):\left(\pi=\frac{22}{7}\right)

  55. Question 55Physics· Wave Optics

    Two wavelengths λ1\lambda_{1} and λ2\lambda_{2} are used in Young's double slit experiment λ1=450 nm\lambda_{1}=450 \mathrm{~nm} and λ2=650 nm\lambda_{2}=650 \mathrm{~nm}. The minimum order of fringe produced by λ2\lambda_{2} which overlaps with the fringe produced by λ1\lambda_{1} is nn. The value of nn is \qquad

  56. Question 56Physics· Newton's Laws of Motion

    An elastic spring under tension of 3 N has a length a. Its length is bb under tension 2 N . For its length (3a−2b)(3 a-2 b), the value of tension will be \qquad N

  57. Question 57Physics· Vectors and Scalars

    Two forces F→1\overrightarrow{\mathrm{F}}_{1} and F→2\overrightarrow{\mathrm{F}}_{2} are acting on a body. One force has magnitude thrice that of the other force and the resultant of the two forces is equal to the force of larger magnitude. The angle between F⃗1\vec{F}_{1} and F⃗2\vec{F}_{2} is cos⁡−1(1n)\cos ^{-1}\left(\frac{1}{n}\right). The value of ∣n∣|n| is \qquad .

  58. Question 58Physics· Rotational Dynamics

    A solid sphere and a hollow cylinder roll up without slipping on same inclined plane with same initial speed vv. The sphere and the cylinder reaches upto maximum heights h1h_{1} and h2h_{2}, respectively, above the initial level. The ratio h1:h2h_{1}: h_{2} is n10\frac{n}{10}. The value of nn is \qquad .

  59. Question 59Chemistry· Electrochemistry

    What pressure (bar) of H2\mathrm{H}_{2} would be required to make emf of hydrogen electrode zero in pure water at 25∘C25^{\circ} \mathrm{C} ?

    1. Option A:

      10−1410^{-14}

    2. Option B:

      10−710^{-7}

    3. Option C:

      1

    4. Option D:

      0.5

  60. Question 60Chemistry· Coordination Compounds

    The correct sequence of ligands in the order of decreasing field strength is :

    1. Option A:

      CO>HX2O>FX−>SX2−\ce{CO > H2O > F^- > S^{2-}}

    2. Option B:

      OHX−>FX−>NHX3>CNX−\ce{OH^- > F^- > NH3 > CN^-}

    3. Option C:

      NCSX−>EDTAX4−>CNX−>CO\ce{NCS^- > EDTA^{4-} > CN^- > CO}

    4. Option D:

      SX2−>OHX−>EDTAX4−>CO\ce{S^{2-} > OH^- > EDTA^{4-} > CO}

  61. Question 61Chemistry· General Organic Chemistry

    What will be the decreasing order of basic strength of the following conjugate bases ?

    −OH,RO,CH3COOˉ,C1‾{ }^{-} \mathrm{OH}, \mathrm{RO}, \mathrm{CH}_{3} \mathrm{CO} \bar{O}, \mathrm{C} \overline{1}

    1. Option A:

      CI‾>OH>RO‾>CH3COO‾\mathrm{C} \overline{\mathrm{I}}>\mathrm{OH}>\mathrm{R} \overline{\mathrm{O}}>\mathrm{CH}_{3} \mathrm{CO} \overline{\mathrm{O}}

    2. Option B:

      RO‾>−OH>CH3COO‾>CI‾\mathrm{R} \overline{\mathrm{O}}>{ }^{-} \mathrm{OH}>\mathrm{CH}_{3} \mathrm{CO} \overline{\mathrm{O}}>\mathrm{C} \overline{\mathrm{I}}

    3. Option C:

      −OH>RO‾>CH3COO‾>C1‾{ }^{-} \mathrm{OH}>\mathrm{R} \overline{\mathrm{O}}>\mathrm{CH}_{3} \mathrm{CO} \overline{\mathrm{O}}>\mathrm{C} \overline{1}

    4. Option D:

      C1‾>RO‾>−OH>CH3COO‾\mathrm{C} \overline{1}>\mathrm{R} \overline{\mathrm{O}}>{ }^{-} \mathrm{OH}>\mathrm{CH}_{3} \mathrm{CO} \overline{\mathrm{O}}

  62. Question 62Chemistry· Practical Inorganic chemistry (Qualitative Analysis)

    In the precipitation of the iron group (III) in qualitative analysis, ammonium chloride is added before adding ammonium hydroxide to :

    1. Option A:

      prevent interference by phosphate ions

    2. Option B:

      decrease concentration of −OH−{ }^{-} \mathrm{OH}^{-}ions

    3. Option C:

      increase concentration of Cl−\mathrm{Cl}^{-}ions

    4. Option D:

      increase concentration of NH4+\mathrm{NH}_{4}{ }^{+}ions

  63. Question 63Chemistry· Electrochemistry

    One of the commonly used electrode is calomel electrode. Under which of the following categories calomel electrode comes?

    1. Option A:

      Metal - Insoluble Salt - Anion electrodes

    2. Option B:

      Oxidation - Reduction electrodes

    3. Option C:

      Gas - Ion electrodes

    4. Option D:

      Metal ion-Metal electrodes

  64. Question 64Chemistry· Coordination Compounds

    Number of complexes from the following with even number of unpaired "d" electrons is \qquad .

    [V(H2O)6]3+,[Cr(H2O)6]2+,[Fe(H2O)6]3+\left[\mathrm{V}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}, \quad\left[\mathrm{Cr}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}, \quad\left[\mathrm{Fe}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+}, [Ni(H2O)6]3+,[Cu(H2O)6]2+\left[\mathrm{Ni}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{3+},\left[\mathrm{Cu}\left(\mathrm{H}_{2} \mathrm{O}\right)_{6}\right]^{2+}

    [Given atomic numbers: V=23,Cr=24,Fe=26\mathrm{V}=23, \mathrm{Cr}=24, \mathrm{Fe}=26, Ni=28,Cu=29]\mathrm{Ni}=28, \mathrm{Cu}=29]

    1. Option A:

      2

    2. Option B:

      4

    3. Option C:

      5

    4. Option D:

      1

  65. Question 65Chemistry· Chemical Bonding

    Which one of the following molecules has maximum dipole moment ?

    1. Option A:

      NF3\mathrm{NF}_{3}

    2. Option B:

      CH4\mathrm{CH}_{4}

    3. Option C:

      NH3\mathrm{NH}_{3}

    4. Option D:

      PF5\mathrm{PF}_{5}

  66. Question 66Chemistry· General Organic Chemistry

    Which among the following is incorrect statement?

    1. Option A:

      Electromeric effect dominates over inductive effect

    2. Option B:

      The electromeric effect is, temporary effect

    3. Option C:

      The organic compound shows electromeric effect in the presence of the reagent only

    4. Option D:

      Hydrogen ion (H+)\left(\mathrm{H}^{+}\right)shows negative electromeric effect

  67. Question 67Chemistry· Aldehydes and Ketones

    Given below are two statements, one is labelled as Statement I and the other is labelled as Statement II.

    Statement I : Acidity of α\alpha-hydrogens of aldehydes and ketones is responsible for Aldol reaction.

    Statement II : Reaction between benzaldehyde and ethanal will NOT give Cross - Aldol product.

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

    1. Option A:

      Both statement I and statement Il are correct.

    2. Option B:

      Statement I is correct and statement Il is incorrect.

    3. Option C:

      Statement I is incorrect and statement Il is correct.

    4. Option D:

      Both statements I and statements ll are incorrect.

  68. Question 68Chemistry· Practical Organic Chemistry

    Which of the following nitrogen containing compound does not give Lassaigne's test?

    1. Option A:

      Phenyl hydrazine

    2. Option B:

      Glycene

    3. Option C:

      Urea

    4. Option D:

      Hydrazine

  69. Question 69Chemistry· d and f Block Elements

    The element which shows only one oxidation state other than its elemental form is :

    1. Option A:

      Cobalt

    2. Option B:

      Scandium

    3. Option C:

      Titanium

    4. Option D:

      Nickel

  70. Question 70Chemistry· Periodicity of Elements and Periodic Properties

    Number of elements from the following that can not form compounds with valencies which match with their respective group valencies is \qquad . B, C, N, S, O, F, P, Al, Si

    1. Option A:

      7

    2. Option B:

      5

    3. Option C:

      6

    4. Option D:

      3

  71. Question 71Chemistry· Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

    The molarity (M)(M) of an aqueous solution containing 5.85 g5.85\ \mathrm{g} of NaCl\mathrm{NaCl} in 500 mL500\ \mathrm{mL} water is:

    (Given : Molar mass of Na=23gmol−1\mathrm{Na} = 23 \mathrm{gmol}^{-1} and Cl=35.5gmol−1\mathrm{Cl} = 35.5 \mathrm{gmol}^{-1} )

    1. Option A:

      20

    2. Option B:

      0.2

    3. Option C:

      2

    4. Option D:

      4

  72. Question 72Chemistry· Alkyl and Aryl Halides

    Identify the correct set of reagents or reaction conditions ' X ' and ' Y ' in the following set of transformation.

    Question 72 figure
    1. Option A:

      X=\mathrm{X}= conc.alc. NaOH,80∘C,Y=Br2/CHCl3\mathrm{NaOH}, 80^{\circ} \mathrm{C}, \mathrm{Y}=\mathrm{Br}_{2} / \mathrm{CHCl}_{3}

    2. Option B:

      X=\mathrm{X}= dil.aq. NaOH,20∘C,Y=HBr/\mathrm{NaOH}, 20^{\circ} \mathrm{C}, \mathrm{Y}=\mathrm{HBr} / acetic acid

    3. Option C:

      X=\mathrm{X}= conc.alc. NaOH,80∘C,Y=HBr\mathrm{NaOH}, 80^{\circ} \mathrm{C}, \mathrm{Y}=\mathrm{HBr} /acetic acid

    4. Option D:

      X=\mathrm{X}= dil.aq. NaOH,20∘C,Y=Br2/CHCl3\mathrm{NaOH}, 20^{\circ} \mathrm{C}, \mathrm{Y}=\mathrm{Br}_{2} / \mathrm{CHCl}_{3}

  73. Question 73Chemistry· Periodicity of Elements and Periodic Properties

    The correct order of first ionization enthalpy values of the following elements is:

    (A) O\mathrm{O} (B) N\mathrm{N} (C) Be\mathrm{Be} (D) F\mathrm{F} (E) B\mathrm{B}

    Choose the correct answer from the options given below:

    1. Option A:

      B << D << C << E << A

    2. Option B:

      E << C << A << B << D

    3. Option C:

      C << E << A << B << D

    4. Option D:

      A << B << D << C << E

  74. Question 74Chemistry· Thermodynamics & Thermochemistry

    The magnitude of enthalpy of formation of (C2H6)\left(\mathrm{C}_{2} \mathrm{H}_{6}\right) from ethylene by addition of hydrogen where the bondenergies of C−H,C−C,H−H\mathrm{C}-\mathrm{H}, \mathrm{C}-\mathrm{C}, \mathrm{H}-\mathrm{H} are 414 kJ,347 kJ414 \mathrm{~kJ}, 347 \mathrm{~kJ}, 615 kJ and 435 kJ respectively is - \qquad kJ

  75. Question 75Chemistry· Aldehydes and Ketones

    The number of correct reaction(s) among the following is \qquad

    Question 75 figure
  76. Question 76Chemistry· Some Basic Concepts of Chemistry (Mole Concept) + Stoichiometry

    Xg\mathrm{X} g of ethylamine is subjected to reaction with NaNO2/HCl\mathrm{NaNO}_{2} / \mathrm{HCl} followed by water and evolved dinitrogen gas which occupied 2.24 L2.24\ \mathrm{L} volume at STP. The value of XX is _____\_\_\_\_\_ ×10−1 g\times 10^{-1} \mathrm{~g}.

  77. Question 77Chemistry· Structure of Atom

    The de-Broglie wavelength of an electron in the 4th 4^{\text {th }} orbit is ____πa0\_\_\_\_ \pi a_0.

    (a0=(a_0 = Bohr radius))

  78. Question 78Chemistry· Redox Reactions

    Only 2 mL of KMnO4\mathrm{KMnO}_{4} solution of unknown molarity is required to reach the end point of a titration of 20 mL of oxalic acid ( 2 M ) in acidic medium. The molarity of KMnO4\mathrm{KMnO}_{4} solution should be \qquad M.

  79. Question 79Chemistry· d and f Block Elements

    Consider the following reaction MnO2+KOH+O2→ A+H2O\mathrm{MnO}_{2}+\mathrm{KOH}+\mathrm{O}_{2} \rightarrow \mathrm{~A}+\mathrm{H}_{2} \mathrm{O}. Product ' AA ' in neutral or acidic medium

    disproportionate to give products ' B ' and ' C ' along with water. The sum of spin-only magnetic moment values of B and C

    is \qquad BM. (nearest integer) (Given atomic number of Mn is 25 )

  80. Question 80Chemistry· Chemical Kinetics

    Consider the following transformation involving first order elementary reaction in each step at constant temperature as

    shown below. A+B⇌ Step 1 Step 3C→ Step 2 P\mathrm{A}+\mathrm{B} \underset{\text { Step } 3}{\stackrel{\text { Step } 1}{\rightleftharpoons}} \mathrm{C} \xrightarrow{\text { Step 2 }} \mathrm{P} Some details of the above reaction are listed below.

    StepRate constant(sec−1)\left( \text{se}{{\text{c}}^{-1}} \right)Activation energy (kJmol−1)\left( \text{kJmo}{{\text{l}}^{-1}} \right)
    1k1{{\text{k}}_{1}}300
    2k2{{\text{k}}_{2}}200
    3k3{{\text{k}}_{3}}Ea3\text{E}{{\text{a}}_{3}}

    if the overall rate constant of the above transformation (k)\left( \text{k} \right) is given as k=k1k2k3\text{k}=\frac{{{\text{k}}_{1}}{{\text{k}}_{2}}}{{{\text{k}}_{3}}} and the overall activation energy

    (Ea)\left( {{\text{E}}_{\text{a}}} \right) is 400  ⁣ ⁣  ⁣ ⁣ kJ  ⁣ ⁣  ⁣ ⁣ mol−1400\text{ }\!\!~\!\!\text{ kJ }\!\!~\!\!\text{ mo}{{\text{l}}^{-1}}, then the value of Ea3\text{E}{{\text{a}}_{3}} is   ⁣ ⁣  ⁣ ⁣ \text{ }\!\!~\!\!\text{ } kJmol−1\text{kJmo}{{\text{l}}^{-1}} (nearest integer)

  81. Question 81Chemistry· Solutions and Colligative Properties

    2.5 g of a non-volatile, non-electrolyte is dissolved in 100 g of water at 25∘C25^{\circ} \mathrm{C}. The solution showed a boiling point elevation by 2∘C2^{\circ} \mathrm{C}. Assuming the solute concentration in negligible with respect to the solvent concentration, the vapour pressure of the resulting aqueous solution is ______ mm of Hg (nearest integer). [Given : Molal boiling point elevation constant of water (Kb)=0.52  K kg mol−1\left(\mathrm{K}_{\mathrm{b}}\right)=0.52 \mathrm\;{K} \mathrm{~kg} \mathrm{~mol}^{-1}, 1 atm pressure =760 mm=760 \mathrm{~mm} of Hg , molar mass of water =18 g mol−1]\left.=18 \mathrm{~g} \mathrm{~mol}^{-1}\right]

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