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JEE Main 2019 (12 Jan Shift 1)

2019 · 90 questions · First 10 Solutions Free
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Q1 mcq
A travelling harmonic wave is represented by the equation $y(x, \,t) = 10^{-3} sin(50t+ 2x),$ where $x$ and $y$ are in meter and $t$ is in seconds. Which of the following is a correct statement about the wave?
a.
The wave is propagating along the positive $x$ - axis with speed $25\,m\,s^{-1}$
b.
The wave is propagating along the positive $x$ - axis with speed $100\,m\,s^{-1}$
c.
The wave is propagating along the negative $x$ - axis with speed $25\,m\,s^{-1}$ Correct Answer
d.
The wave is propagating along the negative $x$ - axis with speed $100\,m\,s^{-1}$

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Q2 mcq
The galvanometer deflection, when key $K_{1}$ is closed but $K_{2}$ is open, equals $\theta _{0}$ (see figure). On closing $K_{2}$ also and adjusting $R_{2}$ to $5\Omega ,$ the deflection in galvanometer becomes $\frac{\theta _{0}}{5}.$ The resistance of the galvanometer is, then, given by [Neglect the internal resistance of battery]:
Question 2 image
a.
$12\Omega$
b.
$22\Omega$ Correct Answer
c.
$5\Omega$
d.
$25\Omega$

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Q3 mcq
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 $P_{1}$ and $P_{2}$ respectively, then:
a.
$P_{1} = 4\,W, \,P_{2} = 16\,W$
b.
$P_{1} = 9\,W, \,P_{2} = 16\,W$
c.
$P_{1} = 16\,W, \,P_{2} = 9\,W$
d.
$P_{1} = 16\,W, \,P_{2} = 4\,W$ Correct Answer

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Q4 mcq
A proton and an $\alpha$ - 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 $r_{p} :r_{\alpha }$ of the circular paths described by them will be:
a.
$1 : 3$
b.
$1 : \sqrt{2}$ Correct Answer
c.
$1 : 2$
d.
$1 : \sqrt{3}$

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Q5 mcq
A satellite of mass $M$ is in a circular orbit of radius $R$ about the center of the earth. A meteorite of the same mass, falling towards the earth, collides with the satellite completely inelastic. The speeds of the satellite and the meteorite are the same, just before the collision. The subsequent motion of the combined body will be:
a.
In an elliptical orbit Correct Answer
b.
Such that it escapes to infinity
c.
In a circular orbit of a different radius
d.
In the same circular orbit of radius $R$

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Q6 mcq
The output of the given logic circuit is:
Question 6 image
a.
$-$ $AB$ Correct Answer
b.
$-$ $A B$ $-$
c.
$AB+AB$
d.
$- -$ $AB + A B$

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Q7 mcq
A $100V$ carrier wave is made to vary between $160\,V$ and $40\,V$ by a modulating signal. What is the modulation index?
a.
$0.3$
b.
$0.6$ Correct Answer
c.
$0.4$
d.
$0.5$

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Q8 mcq
The figure shows a capacitor of capacitance $C$ connected to a battery via a switch, having a total charge $Q$ on it, in steady-state. When the switch $S$ is turned from position $A$ to position $B$ , the energy dissipated in the circuit is
Question 8 image
a.
$\frac{1}{8} \frac{Q^{2}}{C}$
b.
$\frac{3}{8} \frac{Q^{2}}{C}$ Correct Answer
c.
$\frac{3}{4} \frac{Q^{2}}{C}$
d.
$\frac{5}{8} \frac{Q^{2}}{C}$

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Q9 mcq
A simple pendulum, made of a string of length $l$ and $a$ bob of mass $m,$ is released from a small angle $\theta _{0}.$ It strikes a block of mass $M,$ kept on horizontal surface at its lowest point of oscillations, elastically. It bounces back and goes up to an angle $\theta _{1}.$ Then $M$ is given by:
a.
$m( \frac{\theta _{0}-\theta _{1}}{\theta _{0}+\theta _{1}} )$ Correct Answer
b.
$m( \frac{\theta _{0}+\theta _{1}}{\theta _{0}-\theta _{1}} )$
c.
$\frac{m}{2}(\frac{\theta _{0}+\theta _{1}}{\theta _{0}-\theta _{1}})$
d.
$\frac{m}{2}(\frac{\theta _{0}-\theta _{1}}{\theta _{0}+\theta _{1}})$

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Q10 mcq
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 $A+Bx^{2},$ is given by:
a.
$Gm[A(\frac{1}{a+L} - \frac{1}{a})+BL]$
b.
$Gm[A( \frac{1}{a+L} - \frac{1}{a})- BL]$
c.
$Gm[A(\frac{1}{a} - \frac{1}{a+L})- BL]$
d.
$Gm[A( \frac{1}{a} - \frac{1}{a+L})+BL]$ Correct Answer

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Q11 mcq
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 $5\,$ $\mu$ $m$ diameter of a wire is:
a.
$50$
b.
$100$
c.
$500$
d.
$200$
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Q12 mcq
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 $K_{1}$ and that of the outer cylinder is $K_{2}$ . Assuming no loss of heat, the effective thermal conductivity of the system for heat flowing along the length of the cylinder is:
a.
$\frac{2K_{1}+3K_{2}}{5}$
b.
$\frac{K_{1}+K_{2}}{2}$
c.
$K_{1}+K_{2}$
d.
$\frac{K+3K}{4}^{1}^{2}$
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Q13 mcq
In the figure shown, a circuit contains two identical resistors with resistance $R= 5\Omega$ and an inductance with $L= 2mH.$ An ideal battery of $15V$ is connected in the circuit. What will be the current through the battery long after the switch is closed?
Question 13 image
a.
$5.5\,A$
b.
$6\,A$
c.
$3\,A$
d.
$7.5\,A$
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Q14 mcq
A particle $A$ of mass $m$ and charge $q$ is accelerated by a potential difference of $50\,V.$ Another particle $B$ of mass $4m$ and charge $q$ is accelerated by a potential difference of $2500\,V.$ The ratio of de-Broglie wavelengths $\frac{\lambda _{A}}{\lambda _{B}}$ is close to:
a.
$0.07$
b.
$10.00$
c.
$4.47$
d.
$14.14$
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Q15 mcq
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 $30\,\frac{V}{m} ,$ then the amplitude of the electric field for the wave propagating in the glass medium will be:
a.
$30 \frac{V}{m}$
b.
$6\frac{V}{m}$
c.
$24 \frac{V}{m}$
d.
$10\frac{V}{m}$
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Q16 mcq
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 center '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:
Question 16 image
a.
$\frac{1}{2\pi} \sqrt{\frac{3k}{m}}$
b.
$\frac{1}{2\pi} \sqrt{\frac{k}{m}}$
c.
$\frac{1}{2\pi} \sqrt{\frac{6k}{m}}$
d.
$\frac{1}{2\pi} \sqrt{\frac{2k}{m}}$
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Q17 mcq
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:
a.
$16\,cm$
b.
$14\,cm$
c.
$12\,cm$
d.
$18\,cm$
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Q18 mcq
As shown in the figure, two infinitely long, identical wires are bent by $90^{o}$ 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 $OP =OQ= 4cm,$ and the magnitude of the magnetic field at $O$ is $10^{-4} T,$ 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 $(\mu _{0} = 4\pi \times 10^{-7}NA^{-2}):$
Question 18 image
a.
$20\,A,$ perpendicular into the page
b.
$20\,A,$ perpendicular out of the page
c.
$40\,A,$ perpendicualr into the page
d.
$40\,A,$ perpendicular out of the page
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Q19 mcq
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:
a.
$\frac{5}{2}$
b.
$\frac{3}{2}$
c.
$\frac{11}{5}$
d.
$\frac{25}{11}$
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Q20 mcq
An ideal battery of emf $4V$ and resistance $R$ are connected in series in the primary circuit of a potentiometer of length $1\,m$ and resistance $5\Omega .$ The value of $R,$ to give a potential difference of $5\,mV$ across $10\,cm$ of potentiometer wire, is:
a.
$480\Omega$
b.
$495\Omega$
c.
$395\Omega$
d.
$490\Omega$
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Q21 mcq
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:
a.
$\frac{2v}{\sqrt{3}}$
b.
$v$
c.
$\frac{v}{2}$
d.
$\frac{\sqrt{3}}{2}v$
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Q22 mcq
What is the position and nature of image formed by lens combination shown in figure? ( $f_{1}, \,f_{2}$ are focal lengths)
Question 22 image
a.
$40\,cm$ from point $B$ at right; real
b.
$\frac{20}{3}cm$ from point $B$ at right, real
c.
$70\,cm$ from point $B$ at right; real
d.
$70\,cm$ from point $B$ at left; virtual
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Q23 mcq
A particle of mass $m$ moves in a circular orbit in a central potential field $U(r) = \frac{1}{2} kr^{2}.$ If Bohr's quantization conditions are applied, radii of possible orbitals and energy levels vary with quantum number $n$ as:
a.
$r_{n} \propto n^{2}, E_{n} \propto \frac{1}{n^{2}}$
b.
$r_{n} \propto \sqrt{n}, E_{n} \propto n$
c.
$r_{n} \propto n, E_{n} \propto n$
d.
$r_{n} \propto \sqrt{n}, E_{n} \propto \frac{1}{n}$
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Q24 mcq
For the given cyclic process $CAB$ as shown for a gas, the work done is:
Question 24 image
a.
$10\,J$
b.
$5\,J$
c.
$1\,J$
d.
$30\,J$
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Q25 mcq
There is a uniform spherically symmetric surface charge density at a distance $R_{0}$ 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:
Question 25 image
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Q26 mcq
In a meter bridge, the wire of length $1\,m$ has a non-uniform cross-section such that, the variation $\frac{dR}{dl}$ of its resistance $R$ with length $l$ is $\frac{dR}{dl} \propto \frac{1}{\sqrt{l}}.$ Two equal resistances are connected as shown in the figure. The galvanometer has zero deflection when the jockey is at point $P.$ What is the length $AP?$
Question 26 image
a.
$0.2\,m$
b.
$0.35\,m$
c.
$0.3\,m$
d.
$0.25\,m$
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Q27 mcq
A point source of light, S is placed at a distance L in front of the center 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 2L as shown below. The distance over which the man can see the image of the light source in the mirror is:
Question 27 image
a.
$3d$
b.
$2d$
c.
$d$
d.
$\frac{d}{2}$
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Q28 mcq
Determine the electric dipole moment of the system of three charges, placed on the vertices of an equilateral triangle, as shown in the figure:
Question 28 image
a.
$\sqrt{3}ql \frac{ˆj-ˆi}{\sqrt{2}}$
b.
$-\sqrt{3}qlˆj$
c.
$2\,ql ˆj$
d.
$(ql)\frac{ˆi+ˆj}{\sqrt{2}}$
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Q29 mcq
The position vector of the center of mass $\vec{r}_{cm}$ of an asymmetric uniform bar of negligible area of cross-section as shown in figure is:
Question 29 image
a.
$\vec{r}_{cm} = \frac{13}{8} L\hat{x}+ \frac{5}{8} Lˆy$
b.
$\vec{r}_{cm} = \frac{5}{8}L\hat{x}+ \frac{13}{8} Lˆy$
c.
$\vec{r}_{cm} = \frac{3}{8}L\hat{x}+ \frac{11}{8} Lˆy$
d.
$\vec{r}_{cm} = \frac{11}{8} L\hat{x}+ \frac{3}{8} Lˆy$
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Q30 mcq
An ideal gas occupies a volume of $2\,m^{3}$ at a pressure of $3 \times 10^{6} Pa.$ The energy of the gas is:
a.
$10^{8}J$
b.
$9 \times 10^{6}J$
c.
$3 \times 10^{2}J$
d.
$6 \times 10^{4}J$
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Q31 mcq
The major product of the following reaction is:
Question 31 image
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Q32 mcq
The element with $Z = 120$ (not yet discovered) will be a/an
a.
transition metal.
b.
alkaline earth metal.
c.
alkali metal.
d.
inner-transition metal.
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Q33 mcq
$50 mL$ of $0 .5 M$ oxalic acid is needed to neutralize $25 mL$ of sodium hydroxide solution. What is the amount of $NaOH$ in $50 mL$ of the given sodium hydroxide solution?
a.
$2 g$
b.
$4 g$
c.
$1 g$
d.
$8 g$
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Q34 mcq
The increasing order of reactivity of the following compounds towards reaction with alkyl halides directly is: $(i)$ $(ii)\,$ $(iii)$ $(iv)$
Question 34 image
a.
$(i) < (ii) < (iii) < (iv)$
b.
$(ii) < (i) < (iii) < (iv)$
c.
$(ii) < (i) < (iv) < (iii)$
d.
$(i) < (iii) < (iv) < (ii)$
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Q35 mcq
The metal's $d-$ orbitals that are directly facing the ligands in $K_{3}[Co(CN)_{6}]$ are:
a.
$d_{xy},d_{xz}$ and $d_{yz}$
b.
$d_{x^{2}-y^{2}}$ and $d_{z^{2}}$
c.
$d_{xy}$ and $d_{x^{2}-y^{2}}$
d.
$d_{xz},d_{yz}$ and $d_{z^{2}}$
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Q36 mcq
Iodine reacts with concentrated $HNO_{3}$ to yield $Y$ along with other products. The oxidation state of iodine in $Y$ , is:
a.
$1$
b.
$5$
c.
$3$
d.
$7$
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Q37 mcq
Given: On the basis of data given above, predict which of the following gases shows the least adsorption on a definite amount of charcoal?
Question 37 image
a.
$CH_{4}$
b.
$CO_{2}$
c.
$SO_{2}$
d.
$H_{2}$
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Q38 mcq
Decomposition of $X$ exhibits a rate constant of $0 .05$ $\mu$ $g/ year$ . How many years are required for the decomposition of $5$ $\mu$ $g$ of $X$ into $2 .5$ $\mu$ $g$ ?
a.
$20$
b.
4 $0$
c.
$25$
d.
$50$
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Q39 mcq
The pair of metal ions that can give a spin only magnetic moment of $3.9BM$ for the complex $[M(H_{2}O)_{6}]Cl_{2}$ , is:
a.
$Co^{2+}$ and $Fe^{2+}$
b.
$V^{2+}$ and $Fe^{2+}$
c.
$Cr^{2+}$ and $Mn^{2+}$
d.
$V^{2+}$ and $Co^{2+}$
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Q40 mcq
A metal on combustion in excess air forms $X$ . $X$ upon hydrolysis with water yields $H_{2}O_{2}$ and $O_{2}$ along with another product. The metal is:
a.
$Na$
b.
$Mg$
c.
$Li$
d.
$Rb$
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Q41 mcq
The correct order for acid strength of compounds $CH \equiv CH, CH_{3}-C \equiv CH$ and $CH_{2} = CH_{2}$ is as follows:
a.
$CH_{3}-C \equiv CH > CH \equiv CH > CH_{2} = CH_{2}$
b.
$HC \equiv CH > CH_{3}-C \equiv CH > CH_{2} = CH_{2}$
c.
$CH \equiv CH > CH_{2} = CH_{2} > CH_{3}-C \equiv CH$
d.
$CH_{2}-C \equiv CH > CH_{2} = CH_{2} > HC \equiv CH$
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Q42 mcq
Poly- $\beta$ -hydroxybutyrate-co- $\beta$ -hydroxyvalerate $(PHBV)$ is a copolymer of _____.
a.
$3-$ hydroxybutanoic acid and $4-$ hydroxypentanoic acid
b.
$3-$ hydroxybutanoic acid and $2-$ hydroxypentanoic acid
c.
$3-$ hydroxybutanoic acid and $3-$ hydroxypentanoic acid
d.
$2-$ hydroxybutanoic acid and $3-$ hydroxypentanoic acid
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Q43 mcq
The molecule that has minimum or no role in the formation of photochemical smog, is:
a.
$N_{2}$
b.
$O_{3}$
c.
$H_{2}C = O$
d.
$NO$
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Q44 mcq
In the following reaction $^{HCl}Acetal$ $-Aldehyde + Alcohol \rightarrow \rightarrow$ $Aldehyde\, Alcohol$ $HCHO t -BuOH$ $CH_{3}CHO \, MeOH$ The best combination is:
a.
$HCHO$ and $MeOH$
b.
$CH_{3}CHO$ and $t -BuOH$
c.
$CH_{3}CHO$ and $MeOH$
d.
$HCHO$ and $t- BuOH$
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Q45 mcq
The standard electrode potential $E^{o}$ and its temperature coefficient $( \frac{dE}{dT})$ for a cell are $2 V$ and $-5\times 10^{-4} \,V\,K^{-1}$ at $300 K$ , respectively. The reaction is $Zn \,(s) + Cu^{2+} \,(aq) \rightarrow Zn\rightarrow^{2+} \,(aq) + Cu \,(s)$ . The standard reaction enthalpy $(\Delta _{r}H^{-})$ at $300 K$ in $mol^{-1}$ is $[$ Use $R = 8\,J\,K^{-1}\, mol^{-1}$ and $F =96,500\, C mol^{-1}]$
a.
$-412.8$
b.
$206.4$
c.
$-384.0$
d.
$192.0$
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Q46 mcq
Two solids dissociate as follows: $A\,(s) \rightleftharpoons B\,(g) + C\,(g); K_{P_{1}} = x atm^{2}$ $D\,(s) \rightleftharpoons C\,(g) + E\,(g); K_{P_{2}} = y atm^{2}$ The total pressure when both the solids dissociate simultaneously is:
a.
$\sqrt{x + y}\, atm$
b.
$x^{2} + y^{2}\, atm$
c.
$(x + y)\, atm$
d.
$2(\sqrt{x + y})\, atm$
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Q47 mcq
cannot be prepared by:
a.
$HCHO + PhCH(CH_{3}) CH_{2}MgX$
b.
$PhCOCH_{2}CH_{3}+ CH_{3}MgX$
c.
$CH_{3}CH_{2}COCH_{3}+ PhMgX$
d.
$PhCOCH_{3}+ CH_{3}CH_{2}MgX$
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Q48 mcq
Water samples with $BOD$ values of $4$ ppm and $18$ ppm, respectively, are:
a.
Highly polluted and Highly polluted
b.
Clean and Clean
c.
Highly polluted and Clean
d.
Clean and Highly polluted
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Q49 mcq
The freezing point of a $4%$ aqueous solution of $X$ is equal to the freezing point of a $12%$ aqueous solution of $Y$ . If the molecular weight of $X$ is $A$ , then the molecular weight of $Y$ will be
a.
$2A$
b.
$A$
c.
$4A$
d.
$3A$
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Q50 mcq
What is the hardness of a water sample $($ in terms of equivalents of $CaCO_{3})$ containing $10^{-3}M CaSO_{4}$ ? $($ Molar mass of $CaSO_{4} = 136 g mol^{-1})$
a.
$90$ ppm
b.
$50$ ppm
c.
$10$ ppm
d.
$100$ ppm
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Q51 mcq
Among the following compounds most basic amino acid is:
a.
Lysine
b.
Asparagine
c.
Serine
d.
Histidine
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Q52 mcq
$Mn_{2}(CO)_{10}$ is an organometallic compound due to the presence of:
a.
$Mn- O$ bond
b.
$Mn- Mn$ bond
c.
$C- O$ bond
d.
$Mn- C$ bond
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Q53 mcq
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. What are the pressures of the gases for equal number of moles?
a.
$2P_{A} = 3P_{B}$
b.
$P_{A} = 2P_{B}$
c.
$3P_{A} = 2P_{B}$
d.
$P_{A} = 3P_{B}$
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Q54 mcq
In the Hall-Heroult process, aluminium is formed at the cathode. The cathode is made out of:
a.
Platinum
b.
Carbon
c.
Copper
d.
Pure aluminium
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Q55 mcq
For a diatomic ideal gas in a closed system, which of the following plots does not correctly describe the relation between various thermodynamic quantities?
Question 55 image
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Q56 mcq
$o$ What is the work function of the metal if the light of wavelength $4000\,A$ generates photoelectrons of velocity $6 \times 10^{5} ms^{-1}$ from it? (Mass of electron $\, = 9 \times 10^{-31}\, kg$ , velocity of light $= 3 \times 10^{8}\, ms^{-1}$ , Planck's constant $= 6 .626 \times 10^{-34}\, Js$ , Charge of electron $= 6 .626 \times 10^{-34}\, Js$ )
a.
$0 .9 eV$
b.
$4 .0 eV$
c.
$3 .1 eV$
d.
$2 .1 eV$
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Q57 mcq
Among the following four aromatic compounds, which one will have the lowest melting point?
Question 57 image
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Q58 mcq
In the following reactions, products $A$ and $B$ are:
Question 58 image
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Q59 mcq
In a chemical reaction, $A + 2B \rightleftharpoons 2C + D^{K}$ , 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 chemical reaction is:
a.
$1$
b.
$4$
c.
$\frac{1}{4}$
d.
$16$
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Q60 mcq
The major product of the following reaction is:
Question 60 image
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Q61 mcq
The maximum area (in sq. units) of a rectangle having its base on the $x-$ axis and its other two vertices on the parabola, $y= 12 - x^{2}$ such that the rectangle lies inside the parabola, is :
a.
$20\sqrt{2}$
b.
$32$
c.
$36$
d.
$18\sqrt{3}$
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Q62 mcq
Considering only the principal values of inverse functions, the set $A={x\geq 0\, : \, tan^{-1}(2x) + tan^{-1}(3x) = \frac{\pi}{4}}$
a.
Is an empty set
b.
Contains more than two elements
c.
Contains two elements
d.
Is a singleton
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Q63 mcq
An ordered pair $(\alpha , \,\beta )$ for which the system of linear equations $(1 +\alpha )x+\beta y+z= 2$ $\alpha x+ (1 +\beta )y+z= 3$ $\alpha x+\beta y+ 2z= 2$ has a unique solution, is :
a.
$(-3, \,1)$
b.
$(1, \, -3)$
c.
$(2, \,4)$
d.
$(-4, \,2)$
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Q64 mcq
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 ?
a.
$(6, \,5\sqrt{2})$
b.
$(-6, \,2\sqrt{10})$
c.
$(2\sqrt{6}, \,5)$
d.
$(4, \,\sqrt{15})$
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Q65 mcq
If $\lambda$ be the ratio of the roots of the quadratic equation in $x, \,3m^{2}x^{2} +m(m-4)x+ 2 = 0$ , then the least value of $m$ for which $\lambda + \frac{1}{\lambda} = 1$ , is :
a.
$2 - \sqrt{3}$
b.
$-2 + \sqrt{2}$
c.
$4 -2\sqrt{3}$
d.
$4 -3\sqrt{2}$
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Q66 mcq
Let $P(4, -4)$ and $Q(9, 6)$ be two points on the parabola, $y^{2} = 4x$ 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 $\Delta PXQ$ is maximum. Then this maximum area (in sq. units) is :
a.
$\frac{625}{4}$
b.
$\frac{75}{2}$
c.
$\frac{125}{4}$
d.
$\frac{125}{2}$
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Q67 mcq
The area (in sq. units) of the region bounded by the parabola, $y=x^{2} + 2$ and the lines, $y=x+ 1, \,x= 0$ and $x= 3$ , is
a.
$\frac{17}{4}$
b.
$\frac{21}{2}$
c.
$\frac{15}{2}$
d.
$\frac{15}{4}$
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Q68 mcq
Let $S$ be the set of all points in $(-\pi ,\pi )$ at which the function, $f(x) = min{sinx, \, cosx}$ is not differentiable. Then $S$ is a subset of which of the following?
a.
${-\frac{3\pi}{4} , -\frac{\pi}{2}, \frac{\pi}{2}, \frac{3\pi}{4} }$
b.
${- \frac{3\pi}{4}, - \frac{\pi}{4}, \frac{3\pi}{4}, \frac{\pi}{4}}$
c.
${-\frac{\pi}{4}, 0, \frac{\pi}{4}}$
d.
${- \frac{\pi}{2}, -\frac{\pi}{4} , \,\frac{\pi}{4}, \,\frac{\pi}{2}}$
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Q69 mcq
Consider three boxes, each containing $10$ balls labelled $1, \,2, \, … . , \,10$ . Suppose one ball is randomly drawn from each of the boxes. Denote by $n_{i}$ , the label of the ball drawn from the $i^{th}$ box, $(i= 1, \,2, \,3)$ . Then, the number of ways in which the balls can be chosen such that $n_{1} <n_{2} <n_{3}$ is :
a.
$240$
b.
$82$
c.
$120$
d.
$164$
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Q70 mcq
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 :
a.
$28$
b.
$24$
c.
$32$
d.
$36$
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Q71 mcq
If the sum of the deviations of $50$ observations from $30$ is $50$ , then the mean of these observations is :
a.
$30$
b.
$51$
c.
$50$
d.
$31$
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Q72 mcq
If a variable line $3x+ 4y- \lambda = 0$ is such that the two circles $x^{2} +y^{2} -2x-2y+ 1 = 0$ and $x^{2} +y^{2} -18x-2y+ 78 = 0$ are on its opposite sides, then the set of all values of $\lambda$ is the interval :
a.
$[13, \,23]$
b.
$(23, 31)$
c.
$[12, 21]$
d.
$(2, 17)$
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Q73 mcq
Let $S = {1, \,2, \,3, \, … . , 100}$ , then number of non-empty subsets $A$ of $S$ such that the product of elements in $A$ is even is :
a.
$2^{100} -1$
b.
$2^{50} + 1$
c.
$2^{50}(2^{50} -1)$
d.
$2^{50} -1$
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Q74 mcq
The maximum value of $3 cos\theta + 5 sin(\theta - \frac{\pi}{6})$ for any real value of $\theta$ is :
a.
$\sqrt{19}$
b.
$\sqrt{31}$
c.
$\frac{\sqrt{79}}{2}$
d.
$\sqrt{34}$
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Q75 mcq
$_{x}lim_{\rightarrow \rightarrow }\frac{\pi}{4} \frac{cot^{3}x-tanx}{cos(x+^{\pi })}_{4}$ is
a.
$4\sqrt{2}$
b.
$8\sqrt{2}$
c.
$4$
d.
$8$
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Q76 mcq
Let $y=y(x)$ be the solution of the differential equation, $x\frac{dy}{dx} +y=xlog_{e} x, \,(x> 1)$ . If $2y(2) = log_{e}4 -1$ , then $y(e)$ is equal to
a.
$-\frac{e}{2}$
b.
$\frac{e}{4}$
c.
$-\frac{e^{2}}{2}$
d.
$\frac{e^{2}}{4}$
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Q77 mcq
$1 0 0$ $[ ]$ Let $P = 3 1 0$ and $Q= [q_{ij}]$ be two $3 \times 3\,$ matrices such that $Q- P^{5} =I_{3}$ . Then $\frac{q_{21}+q_{31}}{q_{32}}$ is equal to : $[ ]$ $9 3 1$
a.
$10$
b.
$9$
c.
$15$
d.
$135$
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Q78 mcq
Let $C_{1}$ and $C_{2}$ be the centres of the circles $x^{2} +y^{2} -2x-2y-2 = 0$ and $x^{2} +y^{2} -6x-6y+ 14 = 0$ respectively. If $P$ and $Q$ are the points of intersection of these circles, then the area (in sq. units) of the quadrilateral $PC_{1}QC_{2}$ is :
a.
$6$
b.
$4$
c.
$8$
d.
$9$
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Q79 mcq
The Boolean expression $((p\wedge q) \vee (p\vee ~q)) \wedge (~p\wedge ~q)$ is equivalent to
a.
$p\wedge (~q)$
b.
$(~p) \wedge (~q)$
c.
$p\vee (~q)$
d.
$p\wedge q$
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Q80 mcq
The perpendicular distance from the origin to the plane containing the two lines, $\frac{x\,+\,2}{3} = \frac{y\,-\,2}{5} = \frac{z\,+\,5}{7}$ and $\frac{x\,-\,1}{1} = \frac{y\,-\,4}{4} = \frac{z\,+\,4}{7}$ , is
a.
$11\sqrt{6}$
b.
$\frac{11}{\sqrt{6}}$
c.
$11$
d.
$6\sqrt{11}$
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Q81 mcq
The sum of the distinct real values of $\mu$ for which the vectors $\mu ˆi+ ˆj+ ˆk, \,ˆi+\mu ˆj+ ˆk, \,ˆi+ ˆj+\mu ˆk$ are co- planar, is
a.
$0$
b.
$-1$
c.
$1$
d.
$2$
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Q82 mcq
For $x> 1$ , if $(2x)^{2y} = 4e^{2x-2y}$ , then $(1 + log_{e}2x)^{2} \frac{dy}{dx}$ is equal to
a.
$log_{e}2x$
b.
$\frac{xlog_{e}2x-log_{e}2}{x}$
c.
$xlog_{e}2x$
d.
$\frac{xlog_{e}2x+log_{e}2}{x}$
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Q83 mcq
A ratio of the $5^{th}$ term from the beginning to the $5^{th}$ term from the end in the binomial expansion of $10$ $(2\frac{1}{3} + \frac{1}{1}_{2(3)3} )$ is
a.
$1 : 4(16)\frac{1}{3}$
b.
$4(36)\frac{1}{3} : 1$
c.
$2(36) \frac{1}{3} : 1$
d.
$1 : 2(6) \frac{1}{3}$
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Q84 mcq
If the straight line $2x-3y+ 17 = 0$ is perpendicular to the line passing through the points $(7, 17)$ and $(15, \,\beta )$ , then $\beta$ equals :
a.
$-5$
b.
$\frac{35}{3}$
c.
$5$
d.
$-\frac{35}{3}$
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Q85 mcq
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 :
a.
$\frac{150}{6^{5}}$
b.
$\frac{175}{6^{5}}$
c.
$\frac{225}{6^{5}}$
d.
$\frac{200}{6^{5}}$
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Q86 mcq
Let $S_{k} = \frac{1\,+\,2\,+\,3+…+k}{k}$ . If $S_{1}^{2} +S^{2}_{2} + … +S^{2}_{10} = \frac{5}{12}A$ , then $A$ is equal to :
a.
$301$
b.
$303$
c.
$156$
d.
$283$
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Q87 mcq
The integral $\int cos(lnx)dx$ , is equal to
a.
$\frac{x}{2}(cos(lnx) -sin(lnx)) +C$
b.
$x(cos(lnx) -sin(lnx)) +C$
c.
$x(cos(lnx) + sin(lnx)) +C$
d.
$\frac{x}{2} (cos(lnx) + sin(lnx)) +C$
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Q88 mcq
Let $f$ and $g$ be continuous functions on $[0,a]$ such that $f(x) =f(a- x)$ and $g(x) +g(a- x) = 4$ , then $\int _{0}^{a} f(x)g(x)dx$ is equal to
a.
$\int _{0}^{a} f(x)dx$
b.
$-3\int _{0}^{a} f(x)dx$
c.
$4\int _{0}^{a} f(x)dx$
d.
$2\int _{0}^{a} f(x)dx$
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Q89 mcq
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
a.
$cos^{-1}(\frac{7}{31})$
b.
$cos^{-1}(\frac{17}{31} )$
c.
$cos^{-1}(\frac{19}{35})$
d.
$cos^{-1}(\frac{9}{35} )$
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Q90 mcq
If $\frac{z\,-\,\alpha}{z\,+\,\alpha}(\alpha \in R)$ is a purely imaginary number and $|z| = 2$ , then a value of $\alpha$ is :
a.
$1$
b.
$\frac{1}{2}$
c.
$\sqrt{2}$
d.
$2$
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