Joint Entrance Exam |...

13
Vidyamandir Classes VMC | JEE Mains-2019 1 JEE Entrance Examination Joint Entrance Exam | Mains-2019 12 th January 2019 (Morning) | 9.30 AM – 12.30 PM PHYSICS, CHEMISTRY & MATHEMATICS Important Instructions: 1. Immediately fill in the particulars on this page of the Test Booklet with only Black Ball Point Pen provided in the examination hall. 2. The Answer Sheet is kept inside this Test Booklet. When you are directed to open the Test Booklet, take out the Answer Sheet and fill in the particulars carefully. 3. The test is of 3 hours duration. 4. The Test Booklet consists of 90 questions. The maximum marks are 360. 5. There are three parts in the question paper A, B, C consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each question is allotted 4 (four) marks for correct response. 6. Candidate will be awarded marks as stated above in instruction No. 5 for correct response of each question. 1 4 (one-fourth) marks of the total marks allotted to the questions (i.e. 1 mark) will be deducted for indicating incorrect response of each question. No deduction from the total score will be made if no response is indicated for an item in the answer sheet. 7. There is only one correct response for each question. Filling up more than one response in any question will be treated as wrong response and marks for wrong response will be deducted accordingly as per instruction 6 above. 8. For writing particulars/marking responses on Side-1 and Side-2 of the Answer Sheet use only Black Ball Point Pen provided in the examination hall. 9. No candidate is allowed to carry any textual material, printed or written, bits of papers, pager, mobile phone, any electronic device, etc. except the Admit Card inside the examination room/hall. 10. Rough work is to be done on the space provided for this purpose in the Test Booklet only. This space is given at the bottom of each page and in four pages (Page 20-23) at the end of the booklet. 11. On completion of the test, the candidate must hand over the Answer Sheet to the Invigilator on duty in the Room/Hall. However, the candidates are allowed to take away this Test Booklet with them. 12. The CODE for this Booklet is B. Make sure that the CODE printed on Side-2 of the Answer Sheet is same as that on this Booklet. Also tally the serial number of the Test Booklet and Answer Sheet are the same as that on this booklet. In case of discrepancy, the candidate should immediately report the matter to the Invigilator for replacement of both the Test Booklet and the Answer Sheet. 13. Do not fold or make any stray mark on the Answer Sheet.

Transcript of Joint Entrance Exam |...

Page 1: Joint Entrance Exam | Mains-2019100p.s3.amazonaws.com/vidyamandir/JEEMAIN2019JAN/12-Jan-Morning.pdf · The least count of the main scale of a screw gauge is 1 mm. The minimum number

Vidyamandir Classes

VMC | JEE Mains-2019 1 JEE Entrance Examination

Joint Entrance Exam | Mains-2019

12th January 2019 (Morning) | 9.30 AM – 12.30 PM

PHYSICS, CHEMISTRY & MATHEMATICS

Important Instructions: 1. Immediately fill in the particulars on this page of the Test Booklet with only Black Ball Point Pen

provided in the examination hall.

2. The Answer Sheet is kept inside this Test Booklet. When you are directed to open the Test Booklet, take out the Answer Sheet and fill in the particulars carefully.

3. The test is of 3 hours duration.

4. The Test Booklet consists of 90 questions. The maximum marks are 360.

5. There are three parts in the question paper A, B, C consisting of Physics, Chemistry and Mathematics having 30 questions in each part of equal weightage. Each question is allotted 4 (four) marks for correct response.

6. Candidate will be awarded marks as stated above in instruction No. 5 for correct response of each

question. 14 (one-fourth) marks of the total marks allotted to the questions (i.e. 1 mark) will be

deducted for indicating incorrect response of each question. No deduction from the total score will be made if no response is indicated for an item in the answer sheet.

7. There is only one correct response for each question. Filling up more than one response in any question will be treated as wrong response and marks for wrong response will be deducted accordingly as per instruction 6 above.

8. For writing particulars/marking responses on Side-1 and Side-2 of the Answer Sheet use only Black Ball Point Pen provided in the examination hall.

9. No candidate is allowed to carry any textual material, printed or written, bits of papers, pager, mobile phone, any electronic device, etc. except the Admit Card inside the examination room/hall.

10. Rough work is to be done on the space provided for this purpose in the Test Booklet only. This space is given at the bottom of each page and in four pages (Page 20-23) at the end of the booklet.

11. On completion of the test, the candidate must hand over the Answer Sheet to the Invigilator on duty in the Room/Hall. However, the candidates are allowed to take away this Test Booklet with them.

12. The CODE for this Booklet is B. Make sure that the CODE printed on Side-2 of the Answer Sheet is same as that on this Booklet. Also tally the serial number of the Test Booklet and Answer Sheet are the same as that on this booklet. In case of discrepancy, the candidate should immediately report the matter to the Invigilator for replacement of both the Test Booklet and the Answer Sheet.

13. Do not fold or make any stray mark on the Answer Sheet.

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Joint Entrance Exam/IITJEE-2019

PART-A PHYSICS

1. The galvanometer deflection, when key 1K is closed but 2K is open, equals

0 (see figure). On closing 2K also and adjusting 2R to 5 , the deflection

in galvanometer becomes 0 .5 The resistance of the galvanometer is, then,

given by [Neglect the internal resistance of battery] (1) 22 (2) 25 (3) 12 (4) 5

2. The least count of the main scale of a screw gauge is 1 mm. The minimum number of divisions on its circular scale required to measure 5 m diameter of a wire is:

(1) 50 (2) 500 (3) 200 (4) 100

3. In the figure shown, after the switch ‘S’ is turned from position ‘A’ to position ‘B’, the energy dissipated in the circuit in terms of capacitance ‘C’ and total charge ‘Q’ is:

(1) 21

8QC

(2) 25

8QC

(3) 23

4QC

(4) 23

8QC

4. In a meter bridge, the wire of length 1 m has a non-uniform cross-

section such that, the variation dRdl

of its resistance R with length l

is 1 .dRdl l

Two equal resistances galvanometer has zero

deflection when the jockey is at point P. What is the length AP?

(1) 0.25 m (2) 0.2 m (3) 0.3 m (4) 0.35 m

5. A simple pendulum, made of a string of length l and a bob of mass m, is released from a small angle 0 .

It strikes a block of mass M, kept on a horizontal surface at its lowest point of oscillations, elastically. It bounces back and goes up to an angle 1. Then M is given by:

(1) 0 1

0 12m

(2) 0 1

0 1m

(3) 0 1

0 1m

(4) 0 1

0 12m

6. The output of the given logic circuit is:

(1) AB (2) AB AB (3) AB AB (4) AB

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7. What is the position and nature of image formed by lens combination shown in figure? ( 1 2,f f are focal lengths)

(1) 203

cm from point B at right, real

(2) 40 cm from point B at right; real (3) 70 cm from point B at left; virtual (4) 70 cm from point B at right; real

8. A travelling harmonic wave is represented by the equation 3( , ) 10 sin(50 2 ),y x t t x where x and y are in meter and t is in seconds. Which of the following is a correct statement about the wave?

(1) The wave is propagating along the negative x-axis with speed 125 ms

(2) The wave is propagating along the negative x-axis with speed 1100 ms

(3) The wave is propagating along the positive x-axis with speed 1100 ms

(4) The wave is propagating along the positive x-axis with speed 125 ms

9. Two electric bulbs, rated at (25 W, 220 V) and (100 W, 220 V), are connected in series across a 220 V voltage source. If the 25 W and 100 W bulbs draw powers 1P and 2P respectively, then:

(1) 1 216 , 4P W P W (2) 1 29 , 16P W P W

(3) 1 216 , 9P W P W (4) 1 24 , 16P W P W

10. A particle A of mass ‘m’ and charge ‘q’ is accelerated by a potential difference of 50 V. Another particle B of mass ‘4 m’ and charge ‘q’ is accelerated by a potential difference of 2500 V. The ratio of de-Broglie

wavelengths A

B

is close to:

(1) 14.14 (2) 0.07 (3) 10.00 (4) 4.47

11. A person standing on an open ground hears the sound of a jet aeroplane, coming from north at an angle 60° with ground level. But he finds the aeroplane right vertically above his position. If v is the speed of sound, speed of the plane is:

(1) 2v (2) 2

3v (3) 3

2v (4) v

12. A satellite of mass M is in a circular orbit of radius R about the centre of the earth. A meteorite of the same mass, falling towards the earth, collides with the satellite completely inelastically. The speeds of the satellite and the meteorite are the same, just before the collision. The subsequent motion of the combined body will be:

(1) In the same circular orbit of radius R (2) In an elliptical orbit (3) Such that it escapes to infinity (4) In a circular orbit of a different radius

13. An ideal gas occupies a volume of 32 m at a pressure of 63 10 .Pa The energy of the gas is:

(1) 810 J (2) 46 10 J (3) 23 10 J (4) 69 10 J

14. A cylinder of radius R is surrounded by a cylindrical shell of inner radius R and outer radius 2R. The thermal conductivity of the material of the inner cylinder is 1K and that of the outer cylinder is 2.K Assuming no loss of heat, the effective thermal conductivity of the system for heat flowing along the length of the cylinder is:

(1) 1 22 35

K K (2) 1 234

K K (3) 1 2K K (4) 1 2

2K K

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15. The position vector of the centre of mass r cm

of an asymmetric uniform bar of negligible area of cross-section as shown in figure is:

(1) 3 11 8 8

r cm L x L y

(2) 11 3 8 8

r cm L x L y

(3) 13 5 8 8

r cm L x L y

(4) 5 13 8 8

r cm L x L y

16. In the figure shown, a circuit contains two identical resistors with resistance 5 R and an inductance with L = 2 mH. An ideal battery of 15 V is connected in the circuit. What will be the current through the battery long after the switch is closed?

(1) 6 A (2) 3 A (3) 7.5 A (4) 5.5 A

17. Two light identical springs of spring constant k are attached horizontally at the two ends of a uniform horizontal rod AB of length l and mass m. The rod is pivoted at its centre ‘O’ and can rotate freely in horizontal plane. The other ends of the two springs are fixed to rigid supports as shown in figure. The rod is gently pushed through a small angle and released. The frequency of resulting oscillation is:

(1) 1 62

km

(2) 1 32

km

(3) 1 22

km

(4) 12

km

18. An ideal battery of 4 V and resistance R are connected in series in the primary circuit of a potentiometer of length 1 m and resistance 5 . The value of R, to give a potential difference of 5 mV across 10 cm of potentiometer wire, is:

(1) 490 . (2) 480 . (3) 395 . (4) 495 .

19. For the given cyclic process CAB as shown for a gas, the work done is:

(1) 5 J (2) 1 J (3) 30 J (4) 10 J

20. A light wave is incident normally on a glass slab of refractive index 1.5. If 4% of light gets reflected and the amplitude of the electric field of the incident light is 30 V/m, then the amplitude of the electric field for the wave propagating in the glass medium will be:

(1) 10 V/m (2) 30 V/m (3) 24 V/m (4) 6 V/m

21. A passenger train of length 60 m travels at a speed of 80 km/hr. Another freight train of length 120 m travels at a speed of 30 km/hr. The ratio of times taken by the passenger train to completely cross the freight train when : (i) they are moving in the same direction, and (ii) in the opposite directions is:

(1) 52

(2) 115

(3) 32

(4) 2511

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22. A point source of light, S is placed at a distance L in front of the centre of plane mirror of width d which is hanging vertically on a wall. A man walks in front of the mirror along a line parallel to the mirror, at a distance 2 L as shown below. The distance over which the man can see the image of the light source in the mirror is:

(1) d (2) 2d (3) 3 d (4) 2 d

23. A proton and an -particle (with their masses in the ratio of 1 : 4 and charges in the ratio of 1 : 2) are accelerated from rest through a potential difference V. If a uniform magnetic field (B) is set up perpendicular to their velocities, the ratio of the radii :pr r of the circular paths described by them

will be:

(1) 1 : 2 (2) 1: 3 (3) 1 : 3 (4) 1: 2

24. A straight rod of length L extends from x = a to x = L + a. The gravitational force it exerts on a point

mass ‘m’ at x = 0, if the mass per unit length of the rod is 2 ,A Bx is given by:

(1) 1 1Gm A BLa L a

(2) 1 1Gm A BL

a a L

(3) 1 1Gm A BLa L a

(4) 1 1Gm A BL

a a L

25. There is a uniform spherically symmetric surface charge density at a distance 0R from the origin. The charge distribution is initially at rest and starts expanding because of mutual repulsion. The figure that represents best the speed V(R(t)) of the distribution as a function of its instantaneous radius R(t) is

(1) (2) (3) (4)

26. Let the moment of inertia of a hollow cylinder of length 30 cm (inner radius 10 cm and outer radius 20 cm), about its axis be I. The radius of a thin cylinder of the same mass such that its moment of inertia about its axis is also I, is:

(1) 16 cm (2) 18 cm (3) 14 cm (4) 12 cm

27. As shown in the figure, two infinitely long, identical wires are bent by 90° and placed in such a way that the segments LP and QM are along the x-axis, while segments PS and QN are parallel to the y-axis. If OP = OQ = 4 cm,

and the magnitude of the magnetic field at O is 410 ,T and the two wires

carry equal currents (see figure), the magnitude of the current in each wire

and the direction of the magnetic field at O will be 7 20( 4 10 )NA

(1) 40 A, perpendicular into the page (2) 20 A, perpendicular out of the page (3) 40 A, perpendicular out of the page (4) 20 A, perpendicular into the page

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28. A 100 V carrier wave is made to vary between 160 V and 40 V by a modulating signal. What is the modulation index?

(1) 0.6 (2) 0.5 (3) 0.4 (4) 0.3

29. Determine the electric dipole moment of the system of three charges, placed on the vertices of an equilateral triangle, as shown in the figure:

(1) 3 ql j (2)

( )2

i jql

(3) 2ql j (4)

32

j iql

30. A particle of mass m moves in a circular orbit in a central potential field 21( ) .2

U r kr If Bohr’s

quantization conditions are applied, radii of possible orbitals and energy levels vary with quantum number n as:

(1) , n nr n E n (2) 22

1, n nr n En

(3) , n nr n E n (4) 1, n nr n En

PART-B CHEMISTRY

1. The major product of the following reaction is:

(1) (2)

(3)

(4)

2. A metal on combustion in excess air forms X. X upon hydrolysis with water yields 2 2H O and 2O along with another product. The metal is:

(1) Rb (2) Mg (3) Li (4) Na

3. Two solids dissociates as follows

1

2pA(s) B(g) C(g) ; K x atm

2

2pD(s) C(g) E(g) ; K y atm

The total pressure when both the solids dissociate simultaneously is:

(1) 2( x y) atm (2) (x + y) atm (3) x y atm (4) 2 2x y

4. Decomposition of X exhibits a rate constant of 0.05 g/year. How many years are required for the

decomposition of 5 g of X into 2.5 g?

(1) 40 (2) 20 (3) 50 (4) 25

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5. The metal d-orbitals that are directly facing the ligands in 3 6K (Co(CN) ) are:

(1) xz yzd d and 2zd (2) xy xzd d and yzd

(3) 2 2x yd

and 2z

d (4) xyd and 2 2x yd

6. Among the following compounds most basic amino acid is: (1) Asparagine (2) Lysine (3) Histidine (4) Serine

7. The correct order for acid strength of compounds 3CH CH, CH — C CH and 2 2CH CH is as follows:

(1) 2 2 3CH CH CH CH CH — C CH

(2) 3 2 2HC CH CH — C CH CH CH

(3) 3 2 2CH — C CH CH CH CH CH

(4) 3 2 2CH — C CH CH CH HC CH

8. cannot be prepared by:

(1) 3 2HCHO PhCH(CH )CH MgX (2) 3 2 3CH CH COCH PhMgX

(3) 2 3 3PhCOCH CH CH MgX (4) 3 3 2PhCOCH CH CH MgX

9. Given Gas 2H 4CH 2CO 2SO Critical 33 190 304 630 Temperature/K On the basis of data given above, predict which of the following gases shows least adsorption on a

definite amount of charcoal? (1) 2CO (2) 2H (3) 4CH (4) 2SO

10. What is the work function of the metal if the light of wavelength 4000 Å generates photoelectrons of velocity 5 16 10 ms from it?

(Mass of electron 319 10 kg, Velocity of light 8 13 10 ms , Planck’s constant 346.626 10 Js,

Charge of electron 19 11.6 10 Je V ) (1) 2.1 eV (2) 3.1 eV (3) 0.9 eV (4) 4.0 eV

11. 2 10Mn (CO) is an organometallic compound due to the presence of:

(1) Mn — C bond (2) Mn — O bond (3) C — O bond (4) Mn — Mn bond

12. Poly- -hydroxybutyrate-co- -hydroxyvalerate(PHBV) is a copolymer of ________.

(1) 3-hydroxybutanoic acid and 4-hydroxypentanoic acid (2) 2-hydroxybutanoic acid and 3-hydroxypentanoic acid (3) 3-hydroxybutanoic acid and 3-hydroxypentanoic acid (4) 3-hydroxybutanoic acid and 2-hydroxypentanoic acid

13. Water samples with BOD values of 4 ppm and 18 ppm, respectively, are: (1) Clean and clean (2) Highly polluted and clean (3) Highly polluted and highly polluted (4) Clean and highly polluted

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14. The standard electrode potential and its temperature coefficient for a cell are 2V and

4 15 10 VK at 300 K respectively. The cell reaction is 2 2Zn(s) Cu (aq) Zn (aq) Cu(s).

The standard reaction enthalpy at 300 K in kJ 1mol is,

[Use 1 1R 8 JK mol and F = 96,000 C 1mol ] (1) 206.4 (2) – 412.8 (3) – 384.0 (4) 192.0

15. The volume of gas A is twice than that of gas B. The compressibility factor of gas A is thrice than that of gas B at same temperature. The pressures of the gases for equal number of moles are:

(1) A BP 2P (2) A BP 3P (3) A B2P 3P (4) A B3P 2P

16. In the following reactions, products A and B are:

(1)

(2)

(3)

(4)

17. The element with Z = 120 (not yet discovered) will be an/a: (1) Alkaline earth metal (2) Alkali metal (3) Inner-transition metal (4) Transition metal

18. The molecule that has minimum/no role in the formation of photochemical smog, is: (1) NO (2) 2CH O (3) 2N (4) 3O

19. 50 mL of 0.5 M oxalic acid is needed to neutralize 25 mL of sodium hydroxide solution. The amount of NaOH in 50 mL of the given sodium hydroxide solution is:

(1) 80 g (2) 20 g (3) 10 g (4) 4 gm

20. In a chemical reaction, KA 2B 2C D, the initial concentration of B was 1.5 times of the concentration of A, but the equilibrium concentrations of A and B were found to be equal. The equilibrium constant(K) for the aforesaid chemical reaction is:

(1) 1 (2) 16 (3) 14

(4) 4

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21. Freezing point of a 4% aqueous solution of X is equal to freezing point of 12% aqueous solution of Y. If molecular weight of X is A, then molecular weight of Y is:

(1) 3A (2) A (3) 4A (4) 2A

22. The hardness of a water sample (in terms of equivalents of 3CaCO ) containing 3410 M CaSO is:

(molar mass of 14CaSO 136 g mol )

(1) 100 ppm (2) 50 ppm (3) 10 ppm (4) 90 ppm

23. Among the following four aromatic compounds, which one will have the lowest melting point?

(1) (2)

(3)

(4)

24. The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is:

(A) (B)

(C) (D)

(1) (A) < (B) < (C) < (D) (2) (A) < (C) < (D) < (B) (3) (B) < (A) < (D) < (C) (4) (B) < (A) < (C) < (D)

25. Iodine reacts with concentrated 3HNO to yield Y along with other products. The oxidation state of iodine in Y, is

(1) 5 (2) 7 (3) 3 (4) 1

26. In the Hall-Heroult process, aluminium is formed at the cathode. The cathode is made out of: (1) Pure aluminium (2) Carbon (3) Copper (4) Platinum

27. The pair of metal ions that can give a spin-only magnetic of 3.9 BM for the complex 2 6 2[M(H O) ]Cl , is:

(1) 2V and 2Co (2) 2Co and 2Fe

(3) 2V and 2Fe (4) 2Cr and 2Mn

28. In the following reaction, HClAldehyde Alcohol Acetal

Aldehyde Alcohol

HCHO t BuOH

3CH CHO MeOH The best combination is:

(1) HCHO and MeOH (2) 3CH CHO and t BuOH

(3) HCHO and t BuOH (4) 3CH CHO and MeOH

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29. For a diatomic ideal gas in a closed system, which of the following plots does not correctly describe the relation between various thermodynamics quantities?

(1) (2)

(3) (4)

30. The major product of the following reaction is :

(1) (2)

(3) (4)

PART-C MATHEMATICS

1. If the straight line, 2x – 3y + 17 = 0 is perpendicular to the line passing through the points (7, 17) and (15, ), then equal

(1) – 5 (2) 353

(3) 353

(4) 5

2. A ratio of the 5th term from the beginning to the 5th term from the end in the binomial expansion of 10

1/31/3

122(3)

is:

(1) 1/31 : 2(6) (2) 1/31 : 4(16)

(3) 1/32(36) : 1 (4) 1/34(36) : 1

3. Let S be the set of all points in ( , ) at which the function, f (x) = min {sinx, cosx} is not

differentiable. Then S is a subset of which of the following?

(1) 3 3, , ,4 2 2 4

(2) 3 3, , ,

4 4 4 4

(3) , 0,4 4

(4) , , ,

2 4 4 2

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4. An ordered pair ( , ) for which the system of linear equations (1 ) 2x y z (1 ) 3x y z 2 2x y z has a unique solution, is: (1) (2, 4) (2) (– 4, 2) (3) (1, – 3) (4) (– 3, 1)

5. Let P(4, – 4) and Q(9, 6) be two points on the parabola, 2 4y x and let X be any point on the arc POQ of this parabola, where O is the vertex of this parabola, such that the area of PXQ is maximum. Then this maximum area (in square units) is:

(1) 752

(2) 6254

(3) 1254

(4) 1252

6. If the vertices of a hyperbola be at (– 2, 0) and (2, 0) and one of its foci be at (– 3, 0), then which one of the following points does not lie on this hyperbola?

(1) (4, 15) (2) ( 6, 2 10) (3) (6, 5 2) (4) (2 6,5)

7. Let 1C and 2C be the centres of the circles 2 2 2 2 2 0x y x y and 2 2 6 6 14 0x y x y respectively. If P and Q are the points of intersection of these circles, then the area (in square units) of the quadrilateral 1 2PC QC is:

(1) 9 (2) 4 (3) 8 (4) 6

8. Let S = {1, 2, 3, …, 100}. The number of non-empty subsets A of S such that the product of elements in A is even is:

(1) 502 1 (2) 502 1 (3) 1002 1 (4) 50 502 (2 1)

9. If ( )z Rz

is a purely imaginary number and | z | = 2, then a value of is:

(1) 12

(2) 1 (3) 2 (4) 2

10. If be the ratio of the roots of the quadratic equation in x, 2 23 ( 4) 2 0,m x m m x then the least

value of m for which 1 1,

is:

(1) 4 2 3 (2) 2 3 (3) 4 3 2 (4) 2 2

11. The Boolean expression (( ) ( ~ )) (~ ~ )p q p q p q is equivalent to:

(1) (~ ) (~ )p q (2) (~ )p q (3) p q (4) (~ )p q

12. The area (in square units) of the region bounded by the parabola, 2 2y x and the lines, y = x + 1, x = 0 and x = 3, is:

(1) 154

(2) 152

(3) 212

(4) 174

13. Let 1 0 03 1 09 3 1

P

and [ ]ijQ q be two 3 × 3 matrices such that 53.Q P I Then 21 31

32

q qq is equal

to: (1) 10 (2) 9 (3) 135 (4) 15

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14. Let y = y(x) be the solution of the differential equation, log ,( 1).edyx y x x xdx

If 2 (2) log 4 1,ey

then y(e) is equal to:

(1) 4e (2)

2

2e

(3) 2

4e (4)

2e

15. The product of three consecutive terms of a G.P. is 512. If 4 is added to each of the first and the second of these terms, the three terms now form an A.P. Then the sum of the original three terms of the given G.P. is

(1) 24 (2) 28 (3) 36 (4) 32

16. The sum of the distinct real values of , for which the vectors, , , i j k i j k i j k are

co-planar is: (1) 0 (2) – 1 (3) 2 (4) 1

17. For x > 1, if 2 2 2(2 ) 4 ,y x yx e then 2(1 log 2 )edyxdx

is equal to:

(1) log 2 log 2e ex xx (2) log 2e x

(3) log 2 log 2e ex xx (4) log 2ex x

18. The integral cos(log )e x dx is equal to: (where C is a constant of integration)

(1) [cos(log ) sin(log )]e ex x x C (2) [cos(log ) sin(log )]2 e ex x x C

(3) [cos(log ) sin(log )]e ex x x C (4) [sin(log ) cos(log )]2 e ex x x C

19. If the sum of the deviations of 50 observations from 30 is 50, then the mean of these observations is: (1) 30 (2) 51 (3) 31 (4) 50

20. 3

/4

cot tanlimcos

4x

x x

x

is:

(1) 4 2 (2) 8 (3) 4 (4) 8 2

21. The maximum area (in square units) of a rectangle having its base on the x-axis and its other two vertices on the parabola, 212y x such that the rectangle lies inside the parabola, is:

(1) 20 2 (2) 18 3 (3) 32 (4) 36

22. Considering only the principal values of inverse functions, the set

1 10 : tan (2 ) tan (3 )4

A x x x

(1) Is an empty set (2) Contains two elements (3) Contains more than two elements (4) Is a singleton

23. Let 1 2 3 .kkS

k

If 2 2 21 2 10

5 ,12

S S S A then A is equal to:

(1) 156 (2) 283 (3) 303 (4) 301

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24. A tetrahedron has vertices P(1, 2, 1), Q(2, 1, 3), R(– 1, 1, 2) and O(0, 0, 0). The angle between the faces OPQ and PQR is:

(1) 1 9cos35

(2) 1 17cos31

(3) 1 7cos31

(4) 1 19cos35

25. Consider three boxes, each containing 10 balls labelled 1, 2, …,10. Suppose one ball is randomly drawn from each of the boxes. Denote by ,in the label of the ball drawn from the thi box, (i = 1, 2, 3). Then, the

number of ways in which the balls can be chosen such that 1 2 3n n n is:

(1) 120 (2) 240 (3) 164 (4) 82

26. If a variable line, 3 4 0x y is such that the two circles 2 2 2 2 1 0x y x y and 2 2 18 2 78 0x y x y are on its opposite sides, then the set of all values of is the interval:

(1) (2, 17) (2) [13, 23] (3) (23, 31) (4) [12, 21]

27. Let f and g be continuous functions on [0, a] such that f (x) = f (a – x) and ( ) ( ) 4,g x g a x then

0

( ) ( )a

f x g x dx is equal to:

(1) 0

4 ( )a

f x dx (2) 0

( )a

f x dx (3) 0

3 ( )a

f x dx (4) 0

2 ( )a

f x dx

28. In a random experiment, a fair die is rolled until two fours are obtained in succession. The probability that the experiment will end in the fifth throw of the die is equal to:

(1) 52006

(2) 51506

(3) 51756

(4) 52256

29. The perpendicular distance from the origin to the plane containing the two lines, 2 2 53 5 7

x y z

and 1 4 4 ,1 4 7

x y z is

(1) 116

(2) 11 6 (3) 6 11 (4) 11

30. The maximum value of 3cos 5sin6

for any real value of is:

(1) 792

(2) 31 (3) 19 (4) 34