JEE Main 2019 (Online) 10th January Morning Slot
Paper was held on Thu, Jan 10, 2019 3:30 AM
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Chemistry

1
Wilkinson catalyst is : (Et = C2H5)
2
Which of the graphs shown below does not represent the relationship between incident light and the electron ejected from metal surface ?
3
The increasing order of the pKa values of the following compounds is :

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Alcohols, Phenols and Ethers Question 153 English
4
If dichloromethane (DCM) and water (H2O) are used for differential extraction, which one of the following statements is correct ?
5
Liquids A and B form an ideal solution in the entire composition range. At 350 K, the vaapor pressures of pure A and pure B are 7 $$ \times $$ 103 Pa and 12 $$ \times $$ 103 Pa, respectively . The composition of the vapor in equilibriumwith a solution containing 40 mole percent of A at this temperature is :
6
Which dicarboxylic acid in presence of a dehydrating agent is least reactive to give an anhydride?
7
The values of Kp/Kc for the following reactions at 300 K are, respectively : (At 300 K, RT = 24.62 dm3 atm mol–1)

N2(g) + O2(g)  $$\rightleftharpoons$$ 2 NO(g)

N2O4(g)  $$\rightleftharpoons$$   2 NO(g)

N2(g) + 3H2(g) $$\rightleftharpoons$$ 2 NH3(g)
8
The electronegativity of aluminium is similar to :
9
The major product formed in the reaction given below will be :

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Compounds Containing Nitrogen Question 214 English
10
The total number of isomers for a square planar complex
[M(F)(Cl)(SCN)(NO2)] is
11
The type of hybridisation and number of lone pair (s) of electrons of Xe in XeOF4, respectively, are:
12
The effect of lanthanoid contraction in the lanthanoid series of elements by and large means :
13
The decreasing order of ease of alkaline hydrolysis for the following esters in

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Aldehydes, Ketones and Carboxylic Acids Question 241 English
14
Consider the following reduction processes :
Zn2+ + 2e $$ \to $$ Zn(s) ; Eo = – 0.76 V
Ca2+ + 2e $$ \to $$ Ca(s); Eo = –2.87 V
Mg2+ + 2e $$ \to $$ Mg(s) ; Eo = – 2.36 V
Ni2 + 2e $$ \to $$ Ni(s) ; Eo = – 0.25
The reducing power of the metals increases in the order :
15
A process has $$\Delta $$H = 200 J mol–1 and $$\Delta $$S = 40 JK–1 mol–1. Out of the values given below, choose the minimum temperature above which the process will be spontaneous :
16
Which hydrogen in compound (E) is easily replaceable during bromination reaction in presence of light ?

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Haloalkanes and Haloarenes Question 154 English
17
A mixture of 100 m mol of Ca(OH)2 and 2 g of sodium sulphate was dissolved in water and the volume was made up to 100 mL. The mass of calcium sulphate formed and the concentration of OH in resulting solution, respectively, are : (Molar mass of Ca (OH)2, Na2SO4 and CaSO4 are 74, 143 and 136 g mol–1 , respectively; Ksp of Ca(OH)2 is 5.5 × 10–6 )
18
The major product of the following reaction is :

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Hydrocarbons Question 143 English
19
The correct structure of product 'P' in the following reactions is :

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Biomolecules Question 167 English
20
The major product of the following reaction is

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Hydrocarbons Question 144 English
21
Two pi and half sigma bonds are present in :
22
The major product 'X' formed in the following reaction is :

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Alcohols, Phenols and Ethers Question 152 English
23
Consider the given plots for a reaction obeying Arrhenius equation (0oC < T < 300oC) : (K and Ea are rate constant and activation energy, respectively)

JEE Main 2019 (Online) 10th January Morning Slot Chemistry - Chemical Kinetics and Nuclear Chemistry Question 175 English

Choose the correct option :

Mathematics

1
If  $${{dy} \over {dx}} + {3 \over {{{\cos }^2}x}}y = {1 \over {{{\cos }^2}x}},\,\,x \in \left( {{{ - \pi } \over 3},{\pi \over 3}} \right)$$  and  $$y\left( {{\pi \over 4}} \right) = {4 \over 3},$$  then  $$y\left( { - {\pi \over 4}} \right)$$   equals -
2
Let $$\overrightarrow a = 2\widehat i + {\lambda _1}\widehat j + 3\widehat k,\,\,$$   $$\overrightarrow b = 4\widehat i + \left( {3 - {\lambda _2}} \right)\widehat j + 6\widehat k,$$  and  $$\overrightarrow c = 3\widehat i + 6\widehat j + \left( {{\lambda _3} - 1} \right)\widehat k$$  be three vectors such that $$\overrightarrow b = 2\overrightarrow a $$ and $$\overrightarrow a $$ is perpendicular to $$\overrightarrow c $$. Then a possible value of $$\left( {{\lambda _1},{\lambda _2},{\lambda _3}} \right)$$ is :
3
In a class of 140 students numbered 1 to 140, all even numbered students opted Mathematics course, those whose number is divisible by 3 opted Physics course and those whose number is divisible by 5 opted Chemistry course. Then the number of students who did not opt for any of the three courses is
4
Let  $${\rm I} = \int\limits_a^b {\left( {{x^4} - 2{x^2}} \right)} dx.$$  If I is minimum then the ordered pair (a, b) is -
5
A point P moves on the line 2x – 3y + 4 = 0. If Q(1, 4) and R (3, – 2) are fixed points, then the locus of the centroid of $$\Delta $$PQR is a line :
6
An unbiased coin is tossed. If the outcome is a head then a pair of unbiased dice is rolled and the sum of the numbers obtained on them is noted. If the toss of the coin results in tail then a card from a well-shuffled pack of nine cards numbered 1, 2, 3, ……, 9 is randomly picked and the number on the card is noted. The probability that the noted number is either 7 or 8 is :
7
Let  $$f\left( x \right) = \left\{ {\matrix{ {\max \left\{ {\left| x \right|,{x^2}} \right\}} & {\left| x \right| \le 2} \cr {8 - 2\left| x \right|} & {2 < \left| x \right| \le 4} \cr } } \right.$$

Let S be the set of points in the interval (– 4, 4) at which f is not differentiable. Then S
8
For each t $$ \in $$ R , let [t] be the greatest integer less than or equal to t

Then  $$\mathop {\lim }\limits_{x \to 1^ + } {{\left( {1 - \left| x \right| + \sin \left| {1 - x} \right|} \right)\sin \left( {{\pi \over 2}\left[ {1 - x} \right]} \right)} \over {\left| {1 - x} \right|.\left[ {1 - x} \right]}}$$
9
Let z1 and z2 be any two non-zero complex numbers such that   $$3\left| {{z_1}} \right| = 4\left| {{z_2}} \right|.$$  If  $$z = {{3{z_1}} \over {2{z_2}}} + {{2{z_2}} \over {3{z_1}}}$$  then :
10
If 5, 5r, 5r2 are the lengths of the sides of a triangle, then r cannot be equal to :
11
If the line 3x + 4y – 24 = 0 intersects the x-axis at the point A and the y-axis at the point B, then the incentre of the triangle OAB, where O is the origin, is :
12
The sum of all two digit positive numbers which when divided by 7 yield 2 or 5 as remainder is -
13
If the third term in the binomial expansion
of $${\left( {1 + {x^{{{\log }_2}x}}} \right)^5}$$ equals 2560, then a possible value of x is -
14
Let  d $$ \in $$ R, and 

$$A = \left[ {\matrix{ { - 2} & {4 + d} & {\left( {\sin \theta } \right) - 2} \cr 1 & {\left( {\sin \theta } \right) + 2} & d \cr 5 & {\left( {2\sin \theta } \right) - d} & {\left( { - \sin \theta } \right) + 2 + 2d} \cr } } \right],$$

$$\theta \in \left[ {0,2\pi } \right]$$ If the minimum value of det(A) is 8, then a value of d is -
15
Let f : R $$ \to $$ R be a function such that f(x) = x3 + x2f'(1) + xf''(2) + f'''(3), x $$ \in $$ R. Then f(2) equals -
16
The shortest distance between the point  $$\left( {{3 \over 2},0} \right)$$   and the curve y = $$\sqrt x $$, (x > 0), is -
17
If the area enclosed between the curves y = kx2 and x = ky2, (k > 0), is 1 square unit. Then k is -
18
Consider the quadratic equation (c – 5)x2 – 2cx + (c – 4) = 0, c $$ \ne $$ 5. Let S be the set of all integral values of c for which one root of the equation lies in the interval (0, 2) and its other root lies in the interval (2, 3). Then the number of elements in S is -
19
The mean of five observations is 5 and their variance is 9.20. If three of the given five observations are 1, 3 and 8, then a ratio of other two observations is -
20
Let n $$ \ge $$ 2 be a natural number and $$0 < \theta < {\pi \over 2}.$$ Then $$\int {{{{{\left( {{{\sin }^n}\theta - \sin \theta } \right)}^{1/n}}\cos \theta } \over {{{\sin }^{n + 1}}\theta }}} \,d\theta $$ is equal to - (where C is a constant of integration)
21
If the system of equations

x + y + z = 5

x + 2y + 3z = 9

x + 3y + az = $$\beta $$

has infinitely many solutions, then $$\beta $$ $$-$$ $$\alpha $$ equals -

Physics

1
Two guns A and B can fire bullets at speeds 1 km/s and 2 km/s respectively. From a point on a horizontal ground, they are fired in all possible directions. The ratio of maximum areas covered by the bullets fired by the two guns, on the ground is -
2
In a Young’s double slit experiment with slit separation 0.1 mm, one observes a bright fringe at angle $${1 \over {40}}$$ by using light of wavelength $$\lambda $$1. When the light of wavelength $$\lambda $$2 is used a bright fringe is seen at the same angle in the same set up. Given that $$\lambda $$1 and $$\lambda $$2 are in visible range (380 nm to 740 nm), their values are -
3
A parallel plate capacitor is of area 6 cm2 and a separation 3 mm. The gap is filled with three dielectric materials of equal thickness (see figure) with dielectric constants K1 = 10, K2 = 12 and K3 = 14. The dielectric constant of a material which when fully inserted in above capacitor, gives same capacitance would be -

JEE Main 2019 (Online) 10th January Morning Slot Physics - Capacitor Question 142 English
4
A block of mass m is kept on a platform which starts from rest with constant acceleration g/2 upward, as shown in figure. Work done by normal reaction on block in time is -

JEE Main 2019 (Online) 10th January Morning Slot Physics - Work Power & Energy Question 117 English
5
Water flows into a large tank with flat bottom at the rate of 10–4m3s–1. Water is also leaking out of a hole ofarea 1 cm2 at its bottom. If the height of the water in the tank remains steady, then this height is -
6
An insulating thin rod of length $$l$$ has a linear charge density $$\rho \left( x \right)$$ = $${\rho _0}{x \over l}$$ on it. The rod is rotated about an axis passing through the origin (x = 0) and perpendicular to the rod. If the rod makes n rotations per second, then the time averaged magnetic moment of the rod is -
7
A solid metal cube of edge length 2 cm is moving in a positive y-direction at a constant speed of 6 m/s. There is a uniform magnetic field of 0.1 T in the positive z-direction. The potential difference between the two faces of the cube perpendicular to the x-axis, is -
8
A plano convex lens of refractive index $$\mu $$1 and focal length ƒ1 is kept in contact with another plano concave lens of refractive index $$\mu $$2 and focal length ƒ2. If the radius of curvature of their spherical faces is R each and ƒ1 = 2ƒ2, then $$\mu $$1 and $$\mu $$2 are related as -
9
A uniform metallic wire has a resistance of 18 $$\Omega $$ and is bent into an equilateral triangle. Then, the resistance between any two vertices of the triangle is -
10
A heat source at T = 103 K is connected to another heat reservoir at T = 102 K by a copper slab which is 1 mthick. Given that the thermal conductivity of copper is 0.1 WK–1m–1, the energy flux through it in the steady state is -
11
If the magnetic field of a plane electromagnetic wave is given by (the speed of light = 3 × 108 B = 100 × 10–6 sin $$\left[ {2\pi \times 2 \times {{10}^{15}}\left( {t - {x \over c}} \right)} \right]$$ then the maximum electric field associated with it is -
12
A homogeneous solid cylindrical roller of radius R and mass M is pulled on a cricket pitch by a horizontal force. Assuming rolling without slipping, angular acceleration of the cylinder is -
13
A satellite is moving with a constant speed v in circular orbit around the earth. An object of mass ‘m’ is ejected from the satellite such that it just escapes from the gravitational pull of the earth. At the time of ejection, the kinetic energy of the object is -
14
To get output 1 at R, for the given logic gate circuit the input values must be

JEE Main 2019 (Online) 10th January Morning Slot Physics - Semiconductor Question 192 English
15
In the given circuit the cells have zero internal resistance. The currents (in Amperes) passing through resistance R1 and R2 respectively, are -

JEE Main 2019 (Online) 10th January Morning Slot Physics - Current Electricity Question 302 English
16
A charge Q is distributed over three concentric spherical shells of radii a, b, c (a < b < c) such that their surface charge densities are equal to one another. The total potential at a point at distance r from their common centre, where r < a, would be -
17
To mop-clean a floor, a cleaning machine presses a circular mop of radius R vertically down with a total force F and rotates it with a constant angular speed about its axis. If the force F is distributed uniformly over the mop and if coefficient of friction between the mop and the floor is $$\mu $$, the torque, applied by the machine on the mop is -
18
In an electron microscope, the resolution that can be achieved is of the order of the wavelength of electrons used. To resolve a width of 7.5 × 10–12 m, the minimum electron energy required is close to -
19
The density of a material in SI units is 128 kg m–3 . In certain units in which the unit of length is 25 cm and the unit of mass is 50 g, the numerical value of density of the material is -
20
A magnet of total magnetic moment 10-2 $${\widehat i}$$ A-m2 is placed in a time varying magnetic field, B$${\widehat i}$$ (cos $$\omega t$$) where B = 1 Tesla and $$\omega $$ = 0.125 rad/s. The work done for reversing the direction of the magnetic moment at t = 1 second, is -
21
In the cube of side ‘a’ shown in the figure, the vector from the central point of the face ABOD to the central point of the face BEFO will be -

JEE Main 2019 (Online) 10th January Morning Slot Physics - Vector Algebra Question 37 English
22
Two electric dipoles, A, B with respective dipole moments $${\overrightarrow d _A} = - 4qai$$ and $${\overrightarrow d _B} = - 2qai$$ are placed on the x-axis with a separation R, as shown in the figure. The distance from A at which both of them produce the same potential is -

JEE Main 2019 (Online) 10th January Morning Slot Physics - Electrostatics Question 228 English
23
A 2 W carbon resistor is color coded with green, black, red and brown respectively. The maximum current which can be passed through this resistor is -
24
A piece of wood of mass 0.03 kg is dropped from the top of a 100 m height building. At the same time, a bullet of mass 0.02 kg is fired vertically upward, with a velocity 100 ms–1, from the ground. The bullet gets embedded in the wood. Then the maximum height to which the combined system reaches above the top of the building before falling below is - (g = 10 ms–2)
25
A string of length 1 m and mass 5 g is fixed at both ends. The tension in the string is 8.0 N. The string is set into vibration using an external vibrator of frequency 100 Hz. The separation between successive nodes on the string is close to -