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JEE Main 2018 (08 Apr)

2018 · 90 questions · First 10 Solutions Free
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Q1 mcq
Two moles of an ideal monoatomic gas occupies a volume $V$ at $27^{o}C$ . The gas expands adiabatically to a volume $2V$ . Calculate $(a)$ the final temperature of the gas and $(b)$ change in its internal energy.
a.
$(a)195\,K\,\,(b)2.7\, kJ$
b.
$(a)189\,K\,\,(b)2.7\, kJ$
c.
$(a)195\,K\,\,(b) -2.7\, kJ$
d.
$(a)189\,K\,\,(b) -2.7\, kJ$ Correct Answer

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Q2 mcq
The dipole moment of a circular loop carrying a current I, is m and the magnetic field at the centre of the loop is $B_{1}$ . When the dipole moment is doubled by keeping the current constant, the magnetic field at the centre of the loop is $B_{2}$ . The ratio $\frac{B_{1}}{B_{2}}$ is:
a.
$\frac{1}{\sqrt{2}}$
b.
$2$
c.
$\sqrt{3}$
d.
$\sqrt{2}$ Correct Answer

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Q3 mcq
In a potentiometer experiment, it is found that no current passes through the galvanometer when the terminals of the cell are connected across 52 cm of the potentiometer wire. If the cell is shunted by a resistance of $5\,\Omega$ ,a balance is found when the cell is connected across 40 cm of the wire. Find the internal resistance of the cell.
a.
$2.5\,\Omega$
b.
$1\,\Omega$
c.
$1.5\,\Omega$ Correct Answer
d.
$2\,\Omega$

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Q4 mcq
For an RLC circuit driven with voltage of amplitude $v_{m}$ and frequency $\omega$ $_{0} = \frac{1}{\sqrt{LC}}$ the current exhibits resonance. The quality factor, $Q$ is given by
a.
$\frac{CR}{\omega _{0}}$
b.
$\frac{\omega _{0}L}{R}$ Correct Answer
c.
$\frac{\omega _{0}R}{L}$
d.
$\frac{R}{(\omega _{0}C)}$

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Q5 mcq
A particle is moving with a uniform speed in a circular orbit of radius R in a central force inversely proportional to the $n^{th}$ power of R. If the period of rotation of the particle is T, then:
a.
$T \propto R^{n/2}$
b.
$T \propto R^{3/2}$ for any n
c.
$T \propto R\frac{n}{2}^{+1}$
d.
$T \propto R\frac{n+1}{2}$ Correct Answer

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Q6 mcq
A particle is moving in a circular path of radius a under the action of an attractive potential $U = -\frac{k}{2r^{2}}.$ Its total energy is:
a.
$-\frac{3}{2} \frac{k}{a^{2}}$
b.
$-\frac{k}{4a^{2}}$
c.
$\frac{k}{2a^{2}}$
d.
Zero Correct Answer

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Q7 mcq
If the series limit frequency of the Lyman series is $V_{L},$ then the series limit frequency of the Pfund series is:
a.
$\frac{V_{L}}{25}$ Correct Answer
b.
$25\,V_{L}$
c.
$16\,V_{L}$
d.
$\frac{V_{L}}{16}$

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Q8 mcq
An electron from various excited states of hydrogen atom emit radiation to come to the ground state. Let $\lambda _{n}, \,\lambda _{g}$ be the de Broglie wavelength of the electron in the $n^{th}$ state and the ground state respectively. Let $\wedge _{n}$ be the wavelength of the emitted photon in the transition from the $n^{th}$ state to the ground state. For large n, (A, B are constants)
a.
$\wedge ^{2}_{n} ≈ \lambda$
b.
$\wedge _{n} ≈ A+ \frac{B}{\lambda ^{2}_{n}}$ Correct Answer
c.
$\wedge _{n} ≈ A+B\lambda _{n}$
d.
$\wedge ^{2}_{n} ≈ A+B\lambda ^{2}_{n}$

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Q9 mcq
On interchanging the resistances, the balance point of a meter bridge shifts to the left by $10\, cm$ . The resistance of their series combination is $1\,k\Omega$ . How much was the resistance on the left slot before interchanging the resistances?
a.
$910\,\Omega$
b.
$990\,\Omega$
c.
$505\,\Omega$
d.
$550\,\Omega$ Correct Answer

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Q10 mcq
The reading of the ammeter for a silicon diode in the given circuit is:
Question 10 image
a.
$13 .5 \, mA$
b.
$0$
c.
$15\, mA$
d.
$11 .5 \, mA$ Correct Answer

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Q11 mcq
Unpolarized light of intensity $I$ passes through an ideal polariser $A$ . Another identical polariser $B$ is placed behind $A$ . The intensity of light beyond B is found to be $\frac{I}{2}$ . Now another identical polariser $C$ is placed between $A$ and $B$ . The intensity beyond B is now found to be $\frac{I}{8}$ . The angle between polariser $A$ and $C$ is
a.
$60^{\circ}$
b.
$0^{\circ}$
c.
$30^{\circ}$
d.
$45^{\circ}$
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Q12 mcq
In an $A.C.$ circuit, the instantaneous e.m.f. and current are given by, $E = 100 sin 30t,I = 20 sin(30t- \frac{$\pi$}{4})$ . In one cycle of $A.C.$ , the average power consumed by the circuit (in watt) and the watt-less current (in ampere) are, respectively:
a.
$50, 0$
b.
$50, 10$
c.
$\frac{1000}{\sqrt{2}}, \,10$
d.
$\frac{50}{\sqrt{2}}, \,0$
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Q13 mcq
From a uniform circular disc of radius R and mass 9 M, a small disc of radius $\frac{R}{3}$ is removed as shown in the figure. The moment of inertia of the remaining disc about an axis perpendicular to the plane of the disc and passing through centre of disc is:
Question 13 image
a.
$\frac{37}{9}MR^{2}$
b.
$4MR^{2}$
c.
$\frac{40}{9}MR^{2}$
d.
$10MR^{2}$
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Q14 mcq
An electron, a proton and an alpha particle having the same kinetic energy are moving in circular orbits of radii $r_{e}, \,r_{p}, \,r_{\alpha }$ respectively in a uniform magnetic field B. The relation between $r_{e}, \,r_{p}, \,r_{\alpha }$ is:
a.
$r_{e} <r_{\alpha } <r_{p}$
b.
$r_{e} >r_{P} =r_{\alpha }$
c.
$r_{e} <r_{p} =r_{\alpha }$
d.
$r_{e} <r_{p} <r_{\alpha }$
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Q15 mcq
A parallel plate capacitor of capacitance $90\, pF$ is connected to a battery of EMF $20\,V$ . If a dielectric material of dielectric constant $K = \frac{5}{3}$ is inserted between the plates, the magnitude of the induced charge will be:
a.
$0. 9\, nC$
b.
$1. 2\, nC$
c.
$0. 3\, nC$
d.
$2. 4\, nC$
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Q16 mcq
The density of a material, in the shape of a cube, is determined by measuring three sides of the cube and its mass. If the relative errors in measuring the mass and length are $1. 5%$ and $1%$ , respectively, the maximum error in determining the density is:
a.
$6\,%$
b.
$2.5\,%$
c.
$3.5\,%$
d.
$4.5\,%$
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Q17 mcq
A solid sphere of radius r made of a soft material of bulk modulus K is surrounded by a liquid in a cylindrical container. A massless piston of area $a$ floats on the surface of the liquid, covering entire cross-section of cylindrical container. When a mass m is placed on the surface of the piston to compress the liquid, the fractional decrement in the radius of the sphere $(\frac{dr}{r})$ , is:
a.
$\frac{mg}{Ka}$
b.
$\frac{Ka}{mg}$
c.
$\frac{Ka}{3mg}$
d.
$\frac{mg}{3Ka}$
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Q18 mcq
Two batteries with e.m.f. $12\,V$ and $13\,V$ are connected in parallel across a load resistor of $10\,\Omega$ . The internal resistance of the two batteries are $1\,\Omega$ and $2\,\Omega$ respectively. The voltage across the load lies between,
a.
$11. 7\,V$ and $11. 8\,V$
b.
$11. 6\,V$ and $11. 7\,V$
c.
$11. 5\,V$ and $11. 6\,V$
d.
$11. 4\,V$ and $11. 5\,V$
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Q19 mcq
Three concentric metal shells $A, \,B$ and $C$ of respective radii $a, \,b$ and $c\,(a\, < \,b\, < \,c)$ have surface charge densities $+\sigma , \, - \sigma$ and $+\sigma$ respectively. The potential of shell $B$ is:
a.
$\frac{\sigma}{\epsilon _{0}}[\frac{b^{2}-c^{2}}{c} +a]$
b.
$\frac{\sigma}{\epsilon _{0}}[\frac{a^{2}-b^{2}}{a} +c]$
c.
$\frac{\sigma}{\epsilon _{0}}[\frac{a^{2}-b^{2}}{b} +c]$
d.
$\frac{\sigma}{\epsilon _{0}}[\frac{b^{2}-c^{2}}{b} +a]$
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Q20 mcq
A telephonic communication service is working at a carrier frequency of $10\, GHz$ . Only $10%$ of it is utilized for transmission. How many telephonic channels can be transmitted simultaneously if each channel requires a bandwidth of $5\, kHz$ ?
a.
$2 \times 10^{6}$
b.
$2 \times 10^{3}$
c.
$2 \times 10^{4}$
d.
$2 \times 10^{5}$
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Q21 mcq
It is found that if a neutron suffers an elastic collinear collision with a deuterium at rest, the fractional loss of its energy is $P_{d}$ , while for its similar collision with a carbon nucleus at rest, the fractional loss of energy is $P_{c}$ . The values of $P_{d}$ and $P_{c}$ are respectively
a.
$0, \,1$
b.
$0. 89, \,0. 28$
c.
$0. 28, \,0. 89$
d.
$0, \,0$
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Q22 mcq
Seven identical circular planar disks, each of mass M and radius R are welded symmetrically as shown. The moment of inertia of the arrangement about the axis normal to the plane and passing through the point P is:
Question 22 image
a.
$\frac{181}{2} MR^{2}$
b.
$\frac{19}{2} MR^{2}$
c.
$\frac{55}{2}MR^{2}$
d.
$\frac{73}{2}MR^{2}$
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Q23 mcq
The mass of a hydrogen molecule is $3.32 \times 10^{-27\,} kg.$ If $10^{23}$ hydrogen molecules strike, per second, a fixed wall of the area $2\, cm^{2}$ at an angle of $45^{o}$ to the normal, and rebound elastically with a speed of $10^{3}\,m\,s^{-1},$ then the pressure on the wall is nearly:
a.
$4.70 \times 10^{2}\,N\,m^{-2}$
b.
$2.35 \times 10^{3}\,N\,m^{-2}$
c.
$4.70 \times 10^{3}\,N\,m^{-2}$
d.
$2.35 \times 10^{2}\,N\,m^{-2}$
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Q24 mcq
A granite rod of $60\, cm$ length is clamped at its middle point and is set into longitudinal vibrations. The density of granite is $2.7 \times 10^{3}\, kg \,m^{-3}$ and its Young's modulus is $9.27 \times 10^{10}\, Pa$ . What will be the fundamental frequency of the longitudinal vibrations?
a.
$7. 5\, kHz$
b.
$5\, kHz$
c.
$2. 5\, kHz$
d.
$10\, kHz$
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Q25 mcq
A silver atom in a solid oscillates in simple harmonic motion in some direction with a frequency of $10^{12}\,s^{-1}$ . What is the force constant of the bonds connecting one atom with the other? (Mole wt. of silver, $= 108\,g\, mol^{-1}$ and Avogadro number $= 6.02 \times 10^{23}$ )
a.
$5.5\,N\,m^{-1}$
b.
$6.4\,N\,m^{-1}$
c.
$7. 1\,N\,m^{-1}$
d.
$2.2\,N\,m^{-1}$
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Q26 mcq
The angular width of the central maximum in a single slit diffraction pattern is $60^{\circ}$ . The width of the slit is $1\,$ $\mu$ $m$ . The slit is illuminated by monochromatic plane waves. If another slit of the same width is made near it, Young's fringes can be observed on a screen placed at a distance $50 cm$ from the slits. If the observed fringe width is $1 cm$ , what is slit separation distance? (i.e., the distance between the centres of each slit.)
a.
$100\,$ $\mu$ $m$
b.
$25\,$ $\mu$ $m$
c.
$50\,$ $\mu$ $m$
d.
$75\,$ $\mu$ $m$
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Q27 mcq
All the graphs below are intended to represent the same motion. One of them does it incorrectly. Pick it up.
Question 27 image
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Q28 mcq
Two masses $m_{1} = 5\, kg$ and $m_{2} = 10\, kg$ , connected by an inextensible string over a frictionless pulley, are moving as shown in the figure. The coefficient of friction of horizontal surface is $0. 15$ . The minimum weight m that should be put on top of $m_{2}$ to stop the motion is:
Question 28 image
a.
$10 .3 \, kg$
b.
$18 .3 \, kg$
c.
$27 .3 \, kg$
d.
$43 .3 \, kg$
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Q29 mcq
In a collinear collision, a particle with an initial speed $v_{0}$ strikes a stationary particle of the same mass. If the final total kinetic energy is $50%$ greater than the original kinetic energy, the magnitude of the relative velocity between the two particles, after the collision, is
a.
$\frac{v_{0}}{\sqrt{2}}$
b.
$\frac{v_{0}}{4}$
c.
$\sqrt{\,2}\,v_{0}$
d.
$\frac{v_{0}}{2}$
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Q30 mcq
An EM wave from air enters a medium. The electric fields are $\vec{E}_{1} =E_{01}xˆcos[2\pi v( \frac{z}{c} - t)]$ in air and $\vec{E}_{2} =E_{02}xˆcos[k(2z- ct)]$ in medium, where the wave number k and frequency $v$ refer to their values in the air. The medium is non-magnetic. If $\epsilon _{r_{1}}$ and $\epsilon _{r_{2}}$ refer to relative permittivities of air and medium respectively, which of the following options, is correct?
a.
$\frac{\epsilon _{r}_{1}}{\epsilon _{r}_{2\,}} = \frac{1}{2}$
b.
$\frac{\epsilon _{r}_{1}}{\epsilon _{r}_{2\,}} = 4$
c.
$\frac{\epsilon _{r}_{1}}{\epsilon _{r}_{2\,}} = 2$
d.
$\frac{\epsilon _{r}_{1}}{\epsilon _{r}_{2\,}} = \frac{1}{4}$
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Q31 mcq
The compound that does not produce nitrogen gas by thermal decomposition is:
a.
$(NH_{4})_{2}SO_{4}$
b.
$Ba(N_{3})_{2}$
c.
$(NH_{4})_{2}Cr_{2}O_{7}$
d.
$NH_{4}NO_{2}$
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Q32 mcq
Phenol on treatment with $CO_{2}$ in the presence of NaOH followed by acidification produces compound X as the major product. X on treatment with $(CH_{3}CO)_{2}$ O in the presence of catalytic amount of $H_{2}SO_{4}$ produces:
Question 32 image
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Q33 mcq
The major product of the following reaction is:
Question 33 image
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Q34 mcq
The predominant form of histamine present in human blood is $(pK_{a}, \,Histidine = 60)$
Question 34 image
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Q35 mcq
An alkali is titrated against acid with methyl orange as an indicator, which of the following is a correct combination?
a.
$Base Acid End\,point$ $Strong Strong Pink\,to\,colourless$
b.
$Base Acid End\,point$ $Weak Srtong Colourless\,to\,pink$
c.
$Base Acid End\,point$ $Strong strong Pinkish\,red\,to\,yellow$
d.
$Base Acid End\,point$ $Weak Strong Yellow\,to\,pinkish\,red$
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Q36 mcq
The major product formed in the following reaction is:
Question 36 image
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Q37 mcq
Total number of lone pair of electrons in $I_{3}^{-}$ ion is:
a.
$12$
b.
$3$
c.
$6$
d.
$9$
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Q38 mcq
The recommended concentration of fluoride ion in drinking water is up to 1 ppm as fluoride ion is required to make teeth enamel harder by converting $[3 Ca_{3}(PO_{4})_{2}. Ca (OH)_{2}]$ to:
a.
$[3 Ca (OH)_{2}. CaF_{2}]$
b.
$[CaF_{2}]$
c.
$[3(CaF_{2}). Ca (OH)_{2}]$
d.
$[3 Ca_{3}(PO_{4})_{2}. CaF_{2}]$
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Q39 mcq
The ratio of mass percent of $C\, and \,H$ of an organic compound $(C_{X}H_{Y}O_{Z})$ is $6\, : \,1.$ If one molecule of the above compound $(C_{X}H_{Y}O_{Z})$ contains half as much oxygen as required to burn one molecule of compound $C_{X}H_{Y}$ completely to $CO_{2}$ and $H_{2}O.$ The empirical formula of the compound $C_{X}H_{Y}O_{Z}$ is
a.
$C_{2}H_{4}O_{3}$
b.
$C_{3}H_{6}O_{3}$
c.
$C_{2}H_{4}O$
d.
$C_{3}H_{4}O_{2}$
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Q40 mcq
The combustion of benzene $(l)$ gives $CO_{2}(g)$ and $H_{2}O(l).$ Given that heat of combustion of benzene at constant volume is $-3263 .9 \, kJ \, mol^{-1}$ at $25^{\circ}C;$ the heat of combustion $(in \, kJ \, mol^{-1})$ of benzene at constant pressure will be $(R = 8 .314 \, JK^{-1} \, mol^{-1})$
a.
$-3267.6$
b.
$4152.6$
c.
$-452.46$
d.
$3260$
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Q41 mcq
How long (approximate) should water be electrolysed by passing through $100\,amperes \,$ current so that the oxygen released can completely burn $27. 66\,g$ of diborane? (Atomic weight of $B = 10. 8\,u$ )
a.
$1. 6\, hours$
b.
$6. 4\, hours$
c.
$0. 8\, hours$
d.
$3. 2\, hours$
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Q42 mcq
Which type of 'defect' has the presence of cations in the interstitial sites?
a.
Metal deficiency defect
b.
Schottky defect
c.
Vacancy defect
d.
Frenkel defect
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Q43 mcq
An aqueous solution contains $0. 10\,M\,H_{2}S$ and $0. 20\,M\, HCl$ . If the equilibrium constant for the formation of $HS^{-}$ from $H_{2}S$ is $1.0 \times 10^{-7}$ and that of $S^{2-}$ from $HS^{-}$ ions is $1.2 \times 10^{-13}$ , then, the concentration of $S^{2-}$ ions in the aqueous solution is:
a.
$5 \times 10^{-19}$
b.
$5 \times 10^{-8}$
c.
$3 \times 10^{-20}$
d.
$6 \times 10^{-21}$
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Q44 mcq
The oxidation states of $Cr$ in $[Cr (H_{2}O)_{6}] Cl_{3}, \,[Cr (C_{6}H_{6})_{2}]$ and $K_{2}[Cr (CN)_{2}(O)_{2}(O_{2})(NH_{3\,})]$ , respectively, are:
a.
$+3, \,0$ and $+4$
b.
$+3, \, + 4$ and $+6$
c.
$+3, \, + 2$ and $+4$
d.
$+3, \,0$ and $+6$
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Q45 mcq
Consider the following reaction and statements: $[Co (NH_{3})_{4}Br_{2}]^{+} + Br^{-} \rightarrow [Co (NH\rightarrow_{3})_{3}Br_{3}] + NH_{3}$ (i) Two isomers are produced if the reactant complex ion is a cis-isomer. (ii) Two isomers are produced if the reactant complex ion is a trans-isomer. (iii) Only one isomer is produced if the reactant complex ion is a trans-isomer. (iv) Only one isomer is produced if the reactant complex ion is a cis-isomer. The correct statements are
a.
(ii) and (iv)
b.
(i) and (ii)
c.
(i) and (iii)
d.
(iii) and (iv)
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Q46 mcq
Phenol reacts with methyl chloroformate in the presence of $NaOH$ to form product $A. \,A\,$ reacts with $Br_{2}$ to form product $B. \,A\, and \,B$ are respectively
Question 46 image
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Q47 mcq
According to molecular orbital theory, which of the following molecule will not be available?
a.
$H^{2-}_{2}$
b.
$He^{2+}_{2}$
c.
$He^{+}_{2}$
d.
$H^{-}_{2}$
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Q48 mcq
Which of the following are Lewis acids?
a.
$BCl_{3}$ and $AlCl_{3}$
b.
$PH_{3}$ and $BCl_{3}$
c.
$AlCl_{3}$ and $CCl_{4}$
d.
$PH_{3}$ and $CCl_{4}$
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Q49 mcq
At $518^{o}C,$ the rate of decomposition of a sample of gaseous acetaldehyde, initially at a pressure of $363 Torr$ was $1 .00 \, Torr \,s^{-1}$ when $5%$ had reacted and $0 .50 \, Torr \,s^{-1}$ when 33% had reacted. The order of the reaction is:
a.
$0$
b.
$2$
c.
$3$
d.
$1$
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Q50 mcq
Which of the following compounds contain(s) no covalent bond(s)? $KCl, \, PH_{3}, \,O_{2}, \,B_{2}H_{6}, \,H_{2}SO_{4}$
a.
$KCl, \,B_{2}H_{6}$
b.
$KCl, \,B_{2}H_{6}, \, PH_{3}$
c.
$KCl, \,H_{2}SO_{4}$
d.
$KCl$
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Q51 mcq
Hydrogen peroxide oxidises $[Fe (CN)_{6}]^{4-} to \,[Fe (CN)_{6}]^{3-}$ in acidic medium, but reduces $[Fe (CN)_{6}]^{3-} to [Fe (CN)_{6}]^{4-}$ in alkaline medium. The other products formed are, respectively
a.
$H_{2}O\, and \,(H_{2}O + OH^{-})$
b.
$(H_{2}O + O_{2})\, and \,H_{2}O$
c.
$(H_{2}O + O_{2})\, and \,(H_{2}O + OH^{-})$
d.
$H_{2}O\, and \,(H_{2}O + O_{2})$
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Q52 mcq
An aqueous solution contains an unknown concentration of $Ba^{2+}$ . When $50\, mL \, of \,a\,1\,M$ solution of $Na_{2}SO_{4}$ is added, $BaSO_{4}$ just begins to precipitate. The final volume is $500\, mL$ . The solubility product of $BaSO_{4}$ is $1 \times 10^{-10}$ . What is the original concentration of $Ba^{2+}$ ?
a.
$1 .0 \times 10^{-10}M$
b.
$5 \times 10^{-9}M$
c.
$2 \times 10^{-9}M$
d.
$1 .1 \times 10^{-9}M$
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Q53 mcq
Glucose on prolonged heating with $HI$ gives
a.
$6-$ iodohexanal
b.
$n-$ Hexane
c.
$1-$ Hexene
d.
Hexanoic acid
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Q54 mcq
Which of the following salts is the most basic in aqueous solution?
a.
$Pb (CH_{3}COO)_{2}$
b.
$Al (CN)_{3}$
c.
$CH_{3}COOK$
d.
$FeCl_{3}$
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Q55 mcq
Which of the following compounds will be suitable for Kjeldahl's method for nitrogen estimation?
Question 55 image
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Q56 mcq
For $\,1\, molal \,$ aqueous solution of the following compounds, which one will show the highest freezing point?
a.
$[Co (H_{2}O)_{3}Cl_{3}]. 3H_{2}O$
b.
$[Co (H_{2}O)_{6}] Cl_{3}$
c.
$[Co (H_{2}O)_{5}Cl] Cl_{2}. H_{2}O$
d.
$[Co (H_{2}O)_{4}Cl_{2}] Cl. 2H_{2}O$
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Q57 mcq
When metal $M\,$ is treated with $NaOH$ , a white gelatinous precipitate $X\,$ is obtained, which is soluble in excess of $NaOH$ . Compound $X\,$ when heated strongly gives an oxide which is used in chromatography as an adsorbent. The metal $M\,$ is
a.
$Fe$
b.
$Zn$
c.
$Ca$
d.
$Al$
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Q58 mcq
The trans-alkenes are formed by the reduction of alkynes with
a.
$Sn -HCl$
b.
$H_{2}-Pd /C, \, BaSO_{4}$
c.
$NaBH_{4}$
d.
$Na / liq. NH_{3}$
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Q59 mcq
Which of the following lines correctly show the temperature dependence of equilibrium constant $K,$ for an exothermic reaction?
Question 59 image
a.
$A\,&\,D$
b.
$A\,&\,B$
c.
$B\,&\,C$
d.
$C\,&\,D$
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Q60 mcq
The increasing order of basicity of the following compounds is :
Question 60 image
a.
(iv) < (ii) < (i) <(iii)
b.
(i) < (ii) < (iii) < (iv)
c.
(ii) < (i) < (iii) < (iv)
d.
(ii) < (i) < (iv) < (iii)
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Q61 mcq
Tangents are drawn to the hyperbola $4x^{2} - y^{2} = 36$ at the points $P$ and $Q$ . If these tangents intersect at the point $T(0, \,3)$ then the area (in sq. units) of $\Delta PTQ$ is:
a.
$36\sqrt{5}$
b.
$45\sqrt{5}$
c.
$54\sqrt{3}$
d.
$60\sqrt{3}$
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Q62 mcq
A straight line through a fixed point $(2, 3)$ intersects the coordinate axes at distinct points $P$ and $Q$ . If $O$ is the origin and the rectangle $OPRQ$ is completed, then the locus of $R$ is:
a.
$3x+ 2y= 6xy$
b.
$3x+ 2y= 6$
c.
$2x+ 3y=xy$
d.
$3x+ 2y=xy$
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Q63 mcq
$|$ A bag contains $4$ red and $6$ black balls. A ball is drawn at random from the bag, its color is observed and this ball along with two additional balls of the same color are returned to the bag. If now a ball is drawn at random from the bag, then the probability that this drawn ball is red, is:
a.
$\frac{3}{4}$
b.
$\frac{3}{10}$
c.
$\frac{2}{5}$
d.
$\frac{1}{5}$
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Q64 mcq
If $\sum ^{9}_{i=1}(x_{i}-5) = 9$ and $\sum ^{9}_{i=1} (x_{i}-5)^{2} = 45$ , then the standard deviation of the $9$ items $x_{1}, \,x_{2}, … . ,x_{9}$ is
a.
$3$
b.
$9$
c.
$4$
d.
$2$
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Q65 mcq
The integral $\int _{(sin^{5}x+cos^{3}xsin}^{sin}_{2}^{2}_{x}^{x}_{+sin}^{cos}_{3}^{2}_{x}^{x}_{cos^{2}x+cos^{5}x)^{2}}dx$ , is equal to (where $C$ is the constant of integration).
a.
$\frac{-1}{1+cot^{3}x} +C$
b.
$\frac{1}{3(1+tan^{3}x)} +C$
c.
$\frac{-1}{3(1+tan^{3}x)} +C$
d.
$\frac{1}{1+cot^{3}x} +C$
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Q66 mcq
$12$ Let $a_{1}, \,a_{2}, \,a_{3}, … … ,a_{49}$ be in $A.P.$ such that $_{k}\Sigma _{=0}a_{4k+1} = 416$ and $a_{9}+a_{43} = 66.$ If $a^{2}_{1} +a^{2}_{2} + … +a^{2}_{17} = 140m,$ then $m$ is equal to:
a.
$33$
b.
$66$
c.
$68$
d.
$34$
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Q67 mcq
The sum of the co-efficient of all odd degree terms in the expansion of $(x+ \sqrt{x^{3}-1})^{5} +(x- \sqrt{x^{3}-1})^{5}, \,(x> 1)$ is
a.
$2$
b.
$-1$
c.
$0$
d.
$1$
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Q68 mcq
The Boolean expression $~(p\vee q) \vee (~p\wedge q)$ is equivalent to
a.
$~q$
b.
$~p$
c.
$p$
d.
$q$
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Q69 mcq
If $\alpha , \,\beta \in C$ are the distinct roots of the equation $x^{2} - x+ 1 = 0,$ then $\alpha ^{101} +\beta ^{107}$ is equal to
a.
$2$
b.
$-1$
c.
$0$
d.
$1$
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Q70 mcq
Let the orthocentre and centroid of a triangle be $A(-3, \,5)$ and $B(3, \,3)$ respectively. If $C$ is the circumcentre of this triangle, then the radius of the circle having line segment $AC$ as diameter, is:
a.
$\frac{3\sqrt{5}}{2}$
b.
$\sqrt{10}$
c.
$2\sqrt{10}$
d.
$3\sqrt{\frac{5}{2}}$
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Q71 mcq
Let $S ={x\in R\, :x\geq 0\,&\,2 \sqrt{x}-3 + \sqrt{x} (\sqrt{x}-6)+ 6 = 0}$ . Then $S$ :
a.
Contains exactly four elements
b.
Is an empty set
c.
Contains exactly one element
d.
Contains exactly two elements
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Q72 mcq
Let $S ={t\in R:f(x) = |x- \pi |\, \cdot (e^{|x|} -1)sin|x|\,is\,not\,differentiable\,at\,t}.$ Then, the set $S$ is equal to:
a.
${0, \,\pi }$
b.
$\phi$ (an empty set)
c.
${0}$
d.
${\pi }$
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Q73 mcq
$||$ If sum of all the solutions of the equation $8 cosx\cdot (cos(\frac{\pi}{6} +x)\cdot cos( \frac{\pi}{6} - x)- \frac{1}{2})= 1$ in $[0, \,\pi ]$ is $k\pi$ , then $k$ is equal to:
Question 73 image
a.
$\frac{20}{9}$
b.
$\frac{2}{3}$
c.
$\frac{13}{9}$
d.
$\frac{8}{9}$
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Q74 mcq
For each $t\in R,$ let $[t]$ be the greatest integer less than or equal to $t$ . Then $_{x}lim_{\rightarrow 0\rightarrow }_{+}x([\frac{1}{x}]+[\frac{2}{x}]+ … +[\frac{15}{x}])$
a.
does not exist $(in \,R)$
b.
is equal to $0$
c.
is equal to $15$
d.
is equal to $120$
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Q75 mcq
The length of the projection of the line segment joining the points $(5, -1, \,4)$ and $(4, -1, \,3)$ on the plane, $x+y z= 7$ is
a.
$\frac{+}{2}$ $\sqrt{\,} _{3}$
b.
$\frac{2}{\sqrt{3}}$
c.
$\frac{2}{3}$
d.
$\frac{1}{3}$
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Q76 mcq
$PQR$ is a triangular park with $PQ=PR= 200\,m$ . A T.V. tower stands at the mid-point of $QR$ . If the angles of elevation of the top of the tower at $P,Q$ and $R$ are respectively, $45^{\circ}, \,30^{\circ}$ and $30^{\circ}$ , then the height of the tower (in $m$ ) is:
a.
$50\sqrt{2}$
b.
$100$
c.
$50$
d.
$100\sqrt{3}$
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Q77 mcq
Let $A$ be the sum of the first $20$ terms and $B$ be the sum of the first $40$ terms of the series $1^{2} + 2 \cdot 2^{2} + 3^{2} + 2 \cdot 4^{2} + 5^{2} + 2 \cdot 6^{2} + …$ If $B-2A= 100\lambda ,$ then $\lambda$ is equal to :
a.
$496$
b.
$232$
c.
$248$
d.
$464$
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Q78 mcq
Let $\vec{u}$ be a vector coplanar with the vectors $\vec{a}= 2ˆi+ 3ˆj- ˆk$ and $\vec{b}= \,ˆj+ ˆk$ . If $\vec{u}$ is perpendicular to $\vec{a}$ and $\vec{u}\cdot \vec{b}= 24$ , then $\vec{u}^{2}$ is equal to:
a.
$84$
b.
$336$
c.
$315$
d.
$256$
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Q79 mcq
If the tangent at $(1, 7)$ to the curve $x^{2} =y-6$ touch the circle $x^{2} +y^{2} + 16x+ 12y+c= 0$ then the value of $c$ is:
a.
$95$
b.
$195$
c.
$185$
d.
$85$
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Q80 mcq
If $L_{1}$ is the line of intersection of the planes $2x-2y+ 3z-2 = 0, \,x- y+z+ 1 = 0$ and $L_{2}$ is the line of intersection of the planes $x+ 2y- z-3 = 0, \,3x- y+ 2z-1 = 0,$ then the distance of the origin from the plane, containing the lines $L_{1}$ and $L_{2}$ is
a.
$\frac{1}{\sqrt{2}}$
b.
$\frac{1}{4\sqrt{2}}$
c.
$\frac{1}{3\sqrt{2}}$
d.
$\frac{1}{2\sqrt{2}}$
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Q81 mcq
If the curves $y^{2} = 6x, \,9x^{2} +by^{2} = 16$ intersect each other at right angles, then the value of $b$ is:
a.
$\frac{9}{2}$
b.
$6$
c.
$\frac{7}{2}$
d.
$4$
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Q82 mcq
Let $f(x) =x^{2} + \frac{1}{x^{2}}$ and $g(x) =x- \frac{1}{x}, \,x\in R-{-1, \,0, \,1}.$ If $h(x) = \frac{f(x)}{g(x)}$ , then the local minimum value of $h(x)$ is:
a.
$2\sqrt{2}$
b.
$3$
c.
$-3$
d.
$-2\sqrt{2}$
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Q83 mcq
From $6$ different novels and $3$ different dictionaries, $4$ novels and $1$ dictionary are to be selected and arranged in a row on a shelf so that the dictionary is always in the middle. The number of such arrangements is:
a.
At least $750$ but less than $1000$
b.
At least $1000$
c.
Less than $500$
d.
At least $500$ but less than $750$
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Q84 mcq
$| |$ $\frac{\pi}{2}$ The values of $\int \frac{sin^{2}x}{1+2^{x}}dx$ is $-\frac{\pi}{2}$
a.
$\frac{\pi}{4}$
b.
$\frac{\pi}{8}$
c.
$\frac{\pi}{2}$
d.
$4\pi$
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Q85 mcq
Let $y=y(x)$ be the solution of the differential equation $sinx\frac{dy}{dx} +ycosx= 4x, \,x\in (0, \,\pi ).$ If $y( \frac{\pi}{2})= 0,$ then $y(\frac{\pi}{6})$ is equal to
a.
$-\frac{4}{9}\pi ^{2}$
b.
$\frac{4}{9\sqrt{3}}\pi ^{2}$
c.
$\frac{-8}{9\sqrt{3}} \pi ^{2}$
d.
$-\frac{8}{9} \pi ^{2}$
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Q86 mcq
Let $g(x) = cosx^{2}, \,f(x) = \sqrt{x},$ and $\alpha ,\beta (\alpha <\beta )$ be the roots of the quadratic equation $18x^{2} -9\pi x+\pi ^{2} = 0$ . Then the area (in sq. units) bounded by the curve $y= (gof)(x)$ and the lines $x=\alpha ,x=\beta$ and $y= 0,$ is
a.
$\frac{1}{2}(\sqrt{2}-1)$
b.
$\frac{1}{2}(\sqrt{3}-1)$
c.
$\frac{1}{2}(\sqrt{3}+ 1)$
d.
$\frac{1}{2}(\sqrt{3}- \sqrt{2})$
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Q87 mcq
If the system of linear equations $x+ky+ 3z= 0$ $3x+ky-2z= 0$ $2x+ 4y-3z= 0$ has a non-zero solution $(x, \,y, \,z),$ then $\frac{xz}{y^{2}}$ is equal to:
a.
$30$
b.
$-10$
c.
$10$
d.
$-30$
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Q88 mcq
$x-4 2x 2x$ If $2x x-4 2x = (A+Bx)\,(x- A)^{2},$ then the ordered pair $(A, \,B)$ is equal to $2x 2x x-4$
a.
$(4, 5)$
b.
$(-4, -5)$
c.
$(-4, \,3)$
d.
$(-4, \,5)$
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Q89 mcq
Tangent and normal are drawn at $P(16, 16)$ on the parabola $y^{2} = 16x$ , which intersect the axis of the parabola at $A\,&B$ , respectively. If $C$ is the center of the circle through the points $P, \,A\,&B$ and $\angle CPB=\theta ,$ then a value of $tan\theta$ is:
a.
$\frac{4}{3}$
b.
$\frac{1}{2}$
c.
$2$
d.
$3$
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Q90 mcq
Two sets $A$ and $B$ are as under: $A= {(a, \,b) \in R\times R\, : |a-5| < 1\,and\,|b-5| < 1};$ $B={(a, \,b) \in R\times R: 4(a-6)^{2} + 9(b-5)^{2} \leq 36}.$ Then :
a.
neither $A\subset B$ nor $B\subset A$
b.
$B\subset A$
c.
$A\subset B$
d.
$A\cap B=\phi$ (an empty set)
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