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JEE Main 2012 (Offline)

2012 · 90 questions · First 10 Solutions Free
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Q1 mcq
A cylindrical tube, open at both ends, has a fundamental frequency, $f$ , in air. The tube is dipped vertically in water so that half of it is in water. The fundamental frequency of the air-column is now
a.
$f$ Correct Answer
b.
$\frac{f}{2}$
c.
$\frac{3f}{4}$
d.
$2f$

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Q2 mcq
Proton, Deuteron and alpha particle of the same kinetic energy are moving in circular trajectories in a constant magnetic field. The radii of proton, deuteron and alpha particle are respectively $r_{p},r_{d}$ and $r_{\alpha }$ . Which one of the following relations is correct?
a.
$r_{\alpha } =r_{p} =r_{d}$
b.
$r_{\alpha } =r_{p} <r_{d}$ Correct Answer
c.
$r_{\alpha } >r_{d} >r_{p}$
d.
$r_{\alpha } =r_{d} >r_{p}$

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Q3 mcq
Helium gas goes through a cycle $ABCDA$ (consisting of two isochoric and two isobaric lines) as shown in figure. Efficiency of this cycle is nearly: (Assume the gas to be close to ideal gas)
Question 3 image
a.
$15.4%$ Correct Answer
b.
$9.1%$
c.
$10.5%$
d.
$12.5%$

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Q4 mcq
A spectrometer gives the following reading when used to measure the angle of a prism. Main scale reading: $58.5$ degree Vernier scale reading : $09$ divisions Given that $1$ division on main scale corresponds to $0.5$ degree. Total divisions on the vernier scale is $30$ and match with $29$ divisions of the main scale. The angle of the prism from the above data
a.
$58.59^{\circ }$
b.
$58.77^{\circ }$
c.
$58.65^{\circ }$ Correct Answer
d.
$59^{\circ }$

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Q5 mcq
A thin liquid film formed between a U-shaped wire and a light slider supports a weight of $1.5 \times 10^{-2}\,N$ (see figure). The length of the slider is $30\,cm$ and its weight negligible. The surface tension of the liquid film is
Question 5 image
a.
$0.0125\,Nm^{-1}$
b.
$0.1\,Nm^{-1}$
c.
$0.05\,Nm^{-1}$
d.
$0.025\,Nm^{-1}$ Correct Answer

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Q6 mcq
A coil is suspended in a uniform magnetic field, with the plane of the coil parallel to the magnetic lines of force. When a current is passed through the coil it starts oscillating; it is very difficult to stop. But if an aluminium plate is placed near to the coil, it stops. This is due to :
a.
development of air current when the plate is placed.
b.
induction of electrical charge on the plate
c.
shielding of magnetic lines of force as aluminium is a paramagnetic material.
d.
electromagnetic induction in the aluminium plate giving rise to electromagnetic damping. Correct Answer

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Q7 mcq
An object $2.4\,m$ in front of a lens forms a sharp image on a film $12\,cm$ behind the lens. A glass plate $1\,cm$ thick, of refractive index $1.50$ is interposed between lens and film with its plane faces parallel to film. At what distance (from lens) should object be shifted to be in sharp focus on film?
a.
$7.2\,m$
b.
$2.4\,m$
c.
$3.2\,m$
d.
$5.6\,m$ Correct Answer

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Q8 mcq
A particle of mass $m$ is at rest at the origin at time $t = 0$ . It is subjected to a force $F(t) = F_{0}e^{-bt}$ in the $x$ direction. Its speed $v(t)$ is depicted by which of the following curves?
Question 8 image

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Q9 mcq
A diatomic molecule is made of two masses $m_{1}$ and $m_{2}$ which are separated by a distance $r$ . If we calculate its rotational energy by applying Bohr's rule of angular momentum quantization, its energy will be given by ( $n$ is an integer)
a.
$\frac{(m_{1}+m_{2})^{2}n^{2}h^{2}}{2m^{2}m^{2}r^{2}}$ $1 2$
b.
$\frac{n^{2}h^{2}}{2(m_{1}+m_{2})r^{2}}$
c.
$\frac{2n^{2}h^{2}}{(m_{1}+m_{2})r^{2}}$
d.
$\frac{(m_{1}+m_{2})n^{2}h^{2}}{2m_{1}m_{2}r^{2}}$ Correct Answer

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Q10 mcq
This question has statement $1$ and statement $2$ . Of the four choices given after the statements, choose the one that best describes the two statements. An insulating solid sphere of radius $R$ has a uniformly positive charge density $\rho$ . As a result of this uniform charge distribution there is a finite value of electric potential at the centre of the sphere, at the surface of the sphere and also at a point out side the sphere. The electric potential at infinity is zero. Statement $1$ : When a charge $q$ is taken from the centre to the surface of the sphere, its potential energy changes by $\frac{qp}{3\epsilon _{0}}$ Statement $2$ : The electric field at a distance $r(r<R)$ from the centre of the sphere is $\frac{\rho r}{3\epsilon _{0}}$
a.
Statement $1$ is true, Statement $2$ is true, Statement $2$ is not the correct explanation for statement $1$ .
b.
Statement $1$ is true, Statement $2$ is false
c.
Statement $1$ is false, Statement $2$ is true Correct Answer
d.
Statement $1$ is true, Statement $2$ is the correct explanation for statement $1$

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Q11 mcq
A radar has a power of $1\,Kw$ and is operating at a frequency of $10\,GHz$ . It is located on a mountain top of height $500\,m$ . The maximum distance upto which it can detect object located on the surface of the earth (Radius of earth $= 6.4 \times 10^{6}\,m$ ) is
a.
$80\,km$
b.
$16\,km$
c.
$40\,km$
d.
$64\,km$
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Q12 mcq
A liquid in a beaker has temperature $\theta (t)$ at time $t$ and $\theta _{0}$ is temperature of surroundings, then according to Newton's law of cooling the correct graph between $log_{e}(\theta - \theta _{0})$ and $t$ is
Question 12 image
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Q13 mcq
In a uniformly charged sphere of total charge $Q$ and radius $R$ , the electric field $E$ is plotted as a function of distance from the centre. The graph which would correspond to the above will be
Question 13 image
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Q14 mcq
Assume that a neutron breaks into a proton and an electron. The energy released during this process is (Mass of neutron $= 1.6725 \times 10^{-27}\,kg;$ mass of proton $= 1.6725 \times 10^{-27}\,kg;$ mass of electron $= 9 \times 10^{-31} kg)$
a.
$0.73\,MeV$
b.
$7.10\,MeV$
c.
$6.30\,MeV$
d.
$5.4\,MeV$
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Q15 mcq
Two cars of masses $m_{1}$ and $m_{2}$ are moving in circles of radii $r_{1}$ and $r_{2}$ , respectively. Their speeds are such that they make complete circles in the same time $t$ . The ratio of their centripetal acceleration is
a.
$m_{1}r_{1} :m_{2}r_{2}$
b.
$m_{1} :m_{2}$
c.
$r_{1} :r_{2}$
d.
$1 : 1$
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Q16 mcq
A Carnot engine, whose efficiency is $40%$ , takes in heat from a source maintained at a temperature of $500\,K$ It is desired to have an engine of efficiency $60%$ . Then, the intake temperature for the same exhaust (sink) temperature must be
a.
efficiency of Carnot engine cannot be made larger than $50%$
b.
$1200\,K$
c.
$750\,K$
d.
$600\,K$
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Q17 mcq
Resistance of a given wire is obtained by measuring the current flowing in it and the voltage difference applied across it. If the percentage errors in the measurement of the current and the voltage difference are $3%$ each, then error in the value of resistance of the wire is
a.
$6%$
b.
zero
c.
$1%$
d.
$3%$
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Q18 mcq
Hydrogen atom is excited from ground state to another state with principal quantum number equal to $4$ . Then the number of spectral lines in the emission spectra will be
a.
$2$
b.
$3$
c.
$5$
d.
$6$
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Q19 mcq
This question has statement $1$ and statement $2$ . Of the four choices given after the statements, choose the one that best describes the two statements Statement 1 : Davisson - germer experiment established the wave nature of electrons. Statement 2 : If electrons have wave nature, they can interfere and show diffraction.
a.
Statement $1$ is false, Statement $2$ is true
b.
Statement $1$ is true, Statement $2$ is false
c.
Statement $1$ is true, Statement $2$ is the correct explanation for statement $1$
d.
Statement $1$ is true, Statement $2$ is true, Statement $2$ is not the correct explanation for statement $1$ .
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Q20 mcq
A charge $Q$ is uniformly distributed over the surface of non conducting disc of radius $R$ . The disc rotates about an axis perpendicular to its plane and passing through its centre with an angular velocity $\omega$ . As a result of this rotation a magnetic field of induction $B$ is obtained at the centre of the disc. If we keep both the amount of charge placed on the disc and its angular velocity to be constant and vary the radius of the disc then the variation of the magnetic induction at the centre of the disc will be represented by the figure
Question 20 image
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Q21 mcq
A wooden wheel of radius $R$ is made of two semicircular parts (see figure); The two parts are held together by a ring made of a metal strip of cross sectional area S and length $L$ . $L$ is slightly less than $2\pi R$ . To fit the ring on the wheel, it is heated so that its temperature rises by $\Delta T$ and it just steps over the wheel. As it cools down to surrounding temperature, it presses the semicircular parts together. If the coefficient of linear expansion of the metal is $\alpha$ , and its Youngs' modulus is $Y$ , the force that one part of the wheel applies on the other part is :
Question 21 image
a.
$2\pi SY\alpha \Delta T$
b.
$SY\alpha \Delta T$
c.
$\pi SY\alpha \Delta T$
d.
$2SY\alpha \Delta T$
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Q22 mcq
An electromagnetic wave in vacuum has the electric and magnetic fields $\vec{E}$ and $\vec{B}$ , which are always perpendicular to each other. The direction of polarization is given by $\vec{X}$ andthat of wave propagation by $\vec{k}$ . Then:
a.
$\vec{X}\parallel \vec{B}$ and $\vec{k}\parallel \vec{B}\times \vec{E}$
b.
$\vec{X}\parallel \vec{E}$ and $\vec{k}\parallel \vec{E}\times \vec{B}$
c.
$\vec{X}\parallel \vec{B}$ and $\vec{k}\parallel \vec{E}\times \vec{B}$
d.
$\vec{X}\parallel \vec{E}$ and $\vec{k}\parallel \vec{B}\times \vec{E}$
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Q23 mcq
This question has statement $1$ and statement $2$ . Of the four choices given after the statements, choose the one that best describes the two statements. If two springs $S_{1}$ and $S_{2}$ of force constants $k_{1}$ and $k_{2}$ , respectively, are stretched by the same force, it is found that more work is done on spring $S_{1}$ than on spring $S_{2}$ . Statement $1$ : If stretched by the same amount, work done on $S_{1}$ , will be more than that on $S_{2}$ Statement $2 :k_{1} <k_{2}$
a.
Statement $1$ is false, Statement $2$ is true
b.
Statement $1$ is true, Statement $2$ is false
c.
Statement $1$ is true, Statement $2$ is the correct explanation for statement $1$
d.
Statement $1$ is true, Statement $2$ is true, Statement $2$ is not the correct explanation for statement $1$ .
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Q24 mcq
A boy can throw a stone up to a maximum height of $10\,m$ . The maximum horizontal distance that the boy can throw the same stone up to will be
a.
$20\sqrt{2}\,m$
b.
$10\,m$
c.
$10\sqrt{2}\,m$
d.
$20\,m$
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Q25 mcq
Truth table for system of four NAND gates as shown in figure is
Question 25 image
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Q26 mcq
The figure shows an experimental plot for discharging of a capacitor in an $R- C$ circuit. The time constant $τ$ of this circuit lies between:
Question 26 image
a.
$150\,sec$ and $200\,sec$
b.
$0$ and $50\,sec$
c.
$50\,sec$ and $100\,sec$
d.
$100\,sec$ and $150\,sec$
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Q27 mcq
Two electric bulbs marked $25\,W -220\,V$ and $100\,W -220\,V$ are connected in series to a $440\,V$ supply. Which of the bulbs will fuse?
a.
both
b.
$100\,W$
c.
$25\,W$
d.
neither
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Q28 mcq
If a simple pendulum has significant amplitude (up to a factor of $1/e$ of original) only in the period between $t= 0s$ to $t=τs$ , then $τ$ may be called the average life of the pendulum. When the spherical bob of the pendulum suffers a retardation (due to viscous drag) proportional to its velocity, with ' $b$ ' as the constant of proportionality, the average life time of the pendulum is (assuming damping is small) in seconds:
a.
$\frac{0.693}{b}$
b.
$b$
c.
$\frac{1}{b}$
d.
$\frac{2}{b}$
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Q29 mcq
The mass of a spaceship is $1000\,kg$ . It is to be launched from the earth's surface out into free space. The value of ' $g$ ' and ' $R$ ' (radius of earth) are $10\,m/s^{2}$ and $6400\,km$ respectively. The required energy for this work will be ;
a.
$6.4 \times 10^{11}$ Joules
b.
$6.4 \times 10^{8}$ Joules
c.
$6.4 \times 10^{9}$ Joules
d.
$6.4 \times 10^{10}$ Joules
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Q30 mcq
In Young's double slit experiment, one of the slit is wider than other, so that the amplitude of the light from one slit is double of that from other slit. If $I_{m}$ be the maximum intensity, the resultant intensity I when they interfere at phase difference $\phi$ is given by
a.
$\frac{I_{m}}{9}(4 + 5 cos\phi )$
b.
$\frac{l_{m}}{3} (1 + 2 cos^{2} \frac{\phi}{2})$
c.
$\frac{I_{m}}{5}(1 + 4 cos^{2} \frac{\phi}{2} )$
d.
$\frac{I_{m}}{9} (1 + 8 cos^{2} \frac{\phi}{2})$
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Q31 mcq
Which among the following will be named as dibromidobis (ethylene diamine)chromium(III) bromide?
a.
$[Cr(en)_{3}]Br_{3}$
b.
$[Cr(en)_{2}Br_{2}]Br$
c.
$[Cr(\,en\,)Br_{4}]^{-}$
d.
$[Cr(en)Br_{2}]Br$
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Q32 mcq
Aspirin is known as:
a.
Acetyl salicylic acid
b.
Phenyl salicylate
c.
Acetyl salicylate
d.
Methyl salicylic acid
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Q33 mcq
lodoform can be prepared from all except :
a.
Ethyl methyl ketone
b.
Isopropyl alcohol
c.
$3-$ Methyl $-2-$ butanone
d.
Isobutyl alcohol
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Q34 mcq
The pH of a $0.1$ molar solution of the acid $HQ$ is $3$ . The value of the ionization constant, Ka of this acid is :
a.
$3 \times 10^{-1}$
b.
$1 \times 10^{-3}$
c.
$1 \times 10^{-5}$
d.
$1 \times 10^{-7}$
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Q35 mcq
The increasing order of the ionic radii of the given isoelectronic species is :
a.
$Cl^{-}, Ca^{2+}, K^{+}, S^{2-}$
b.
$S^{2-}, Cl^{-}, Ca^{2+}, K^{+}$
c.
$Ca^{2+}, K^{+}, Cl^{-}, S^{2-}$
d.
$K^{+}, S^{2-}, Ca^{2+}, Cl^{-}$
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Q36 mcq
For a first order reaction, $(A) \rightarrow \rightarrow$ products, the concentration of $A$ changes from $0.1\,M$ to $0.025\,M$ in $40$ minutes. The rate of reaction when the concentration of $A$ is $0.01\,M$ is :
a.
$1.73 \times 10^{-5}M/min$
b.
$3.47 \times 10^{-4}M/min$
c.
$3.47 \times 10^{-5}M/min$
d.
$1.73 \times 10^{-4}M/min$
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Q37 mcq
How many chiral compounds are possible on monochlorination of $2-$ methyl butane ?
a.
$8$
b.
$2$
c.
$4$
d.
$6$
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Q38 mcq
The incorrect expression among the following is :
a.
$\frac{\Delta G_{system\,}}{\Delta S_{total\,}} = -T$
b.
In isothermal process $w_{reversible\,} = -nRTln \frac{V_{f}}{V_{i}}$
c.
$ln K = \frac{\Delta H^{0}-T\Delta S^{0}}{RT}$
d.
$K = e^{-\Delta G^{0}/RT}$
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Q39 mcq
Which one of the following statements is correct? (1) All amino acids except lysine are optically active (2) All amino acids are optically active (3) All amino acids except glycine are optically (4) All amino acids except glutamic acid are active optically active
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Q40 mcq
The standard reduction potentials for $Zn^{2+}/Zn, Ni^{2+}/Ni$ , and $Fe^{2+}/Fe$ are $-0.76, -0.23$ and $-0.44\,V$ respectively. The reaction $X + Y^{2+} \rightarrow X\rightarrow^{2+} + Y$ will be spontaneous when:
a.
$X =Ni,Y =Fe$
b.
$X =Ni,Y =Zn$
c.
$X =Fe,Y =Zn$
d.
$X =Zn,Y =Ni$
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Q41 mcq
The molecule having smallest bond angle is :
a.
$NCl_{3}$
b.
$AsCl_{3}$
c.
$SbCl_{3}$
d.
$PCl_{3}$
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Q42 mcq
The equilibrium constant $(K_{c})$ for the reaction $N_{2}(g) + O_{2}(\,g) \rightarrow 2NO(g)\rightarrow$ at temperature $T$ is $4 \times 10^{-4}$ . The value of $K_{c}$ for the reaction, $NO(g) \rightarrow 1/2\,N\rightarrow_{2}(g) + 1/2\,O_{2}(g)$ at the same temperature is :
a.
$0.02$
b.
$2.5 \times 10^{2}$
c.
$4 \times 10^{-4}$
d.
$50.0$
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Q43 mcq
$K_{f}$ for water is $1.86\,K\,kg\,mol^{-1}$ . If your automobile radiator holds $1.0\,kg$ of water, how many grams of ethylene glycol $(C_{2}H_{6}O_{2})$ must you add to get the freezing point of the solution lowered to $-2.8^{\circ }C$ ?
a.
$72\,g$
b.
$93\,g$
c.
$39\,g$
d.
$27\,g$
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Q44 mcq
The density of a solution prepared by dissolving $120\,g$ of urea (mol. Mass $= 60u$ ) in $1000\,g$ of water is $1.15\,g/mL$ . The molarity of this solution is :
a.
$0.50\,M$
b.
$1.78\,M$
c.
$1.02\,M$
d.
$2.05\,M$
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Q45 mcq
Which method of purification is represented by the following equation: $Ti(s) + 2I_{2}(g)^{523\,K}\longrightarrow TiI_{4}(g)^{1700\,K}\longrightarrow Ti(s) + 2I_{2}(g)$
a.
zone refining
b.
cupellation
c.
Poling
d.
Van Arkel
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Q46 mcq
In the given transformation, which of the following is the most appropriate reagent?
Question 46 image
a.
$(-)$ $NH_{2}NH_{2}, OH$
b.
$Zn -Hg/HCl$
c.
$Na$ , Liq. $NH_{3}$
d.
$NaBH_{4}$
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Q47 mcq
Ortho-Nitrophenol is less soluble in water than $p-$ and $m-$ Nitrophenols because :
a.
$o-$ Nitrophenol is more volatile in steam than those of $m-$ and $p-$ isomers
b.
$o-$ Nitrophenol shows Intramolecular $H-$ bonding
c.
$o-$ Nitrophenol shows Intermolecular $H-$ bonding
d.
Melting point of $o-$ Nitrophenol is lower than those of $m-$ and $p-$ isomers.
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Q48 mcq
Lithium forms body centred cubic structure. The length of the side of its unit cell is $351pm$ . Atomic radius of the lithium will be:
a.
$75\,pm$
b.
$300\,pm$
c.
$240\,pm$
d.
$152\,pm$
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Q49 mcq
In which of the following pairs the two species are not isostructural?
a.
$CO^{2-}_{3}$ and $NO^{-}_{3}$
b.
$PCl^{+}_{4}$ and $SiCl_{4}$
c.
$PF_{5}$ and $BrF_{5}$
d.
$AlF^{3-}_{6}$ and $SF_{6}$
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Q50 mcq
The electrons identified by quantum numbers $n$ and $I$ : (a) $n= 4,I = 1$ (b) $n= 4,l= 0$ (c) $n= 3,I = 2$ (d) $n= 3,I = 1$ Can be placed in order of increasing energy as:
a.
(c) $<$ (d) $<$ (b) $<$ (a)
b.
(d) $<$ (b) $<$ (c) $<$ (a)
c.
(b) $<$ (d) $<$ (a) $<$ (c)
d.
(a) $<$ (c) $<$ (b) $<$ (d)
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Q51 mcq
Which of the following on thermal decomposition yields a basic as well as an acidic oxide ?
a.
$NaNO_{3}$
b.
$KClO_{3}$
c.
$CaCO_{3}$
d.
$NH_{4}NO_{3}$
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Q52 mcq
$2-$ Hexyne gives trans $-2-$ Hexene on treatment with :
a.
$Pt/H_{2}$
b.
$Li/NH_{3}$
c.
$Pd/BaSO_{4}$
d.
$LiAlH_{4}$
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Q53 mcq
Which branched chain isomer of the hydrocarbon with molecular mass $72\,u$ gives only one isomer of mono substituted alky halide?
a.
Tertiary butyl chloride
b.
Neopentane
c.
Isohexane
d.
Neohexane
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Q54 mcq
Iron exhibits $+2$ and $+3$ oxidation states. Which of the following statements about iron is incorrect?
a.
Ferrous oxide is more basic in nature than the ferric oxide.
b.
Ferrous compounds are relatively more ionic than the corresponding ferric compounds
c.
Ferrous compounds are less volatile than the corresponding ferric compounds.
d.
Ferrous compounds are more easily hydrolysed than the corresponding ferric compounds.
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Q55 mcq
Very pure hydrogen $(99.9%)$ can be made by which of the following processes?
a.
Reaction of methane with steam
b.
Mixing natural hydrocarbons of high molecular weight
c.
Electrolysis of water
d.
Reaction of salt like hydrides with water
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Q56 mcq
Which of the following compounds can be detected by Molisch's test ?
a.
Nitro compounds
b.
Sugars
c.
Amines
d.
Primary alcohols
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Q57 mcq
What is DDT among the following :
a.
Greenhouse gas
b.
A fertilizer
c.
Biodegradable pollutant
d.
Non-biodegradable pollutant
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Q58 mcq
The compressibility factor for a real gas at high pressure is :
a.
$1 + RT/pb$
b.
$1$
c.
$1 + pb/RT$
d.
$1 -pb/RT$
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Q59 mcq
The species which can best serve as an initiator for the cationic polymerization is :
a.
$LiAlH_{4}$
b.
$HNO_{3}$
c.
$AlCl_{3}$
d.
$BuLi$
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Q60 mcq
According to Freundlich adsorption isotherm, which of the following is correct ?
a.
$\frac{x}{m} \propto P^{0}$
b.
$\frac{x}{m} \propto p^{1}$
c.
$\frac{x}{m} \propto p^{1/n}$
d.
All the above are correct for different ranges of pressure
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Q61 mcq
Three numbers are chosen at random without replacement from ${1, 2, 3, … . .8}$ . The probability that their minimum is $3$ , given that their maximum is $6$ , is
a.
$\frac{3}{8}$
b.
$\frac{1}{5}$
c.
$\frac{1}{4}$
d.
$\frac{2}{5}$
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Q62 mcq
If $f : R \rightarrow R\rightarrow$ is a function defined by $f(x) = [x] cos(\frac{2x-1}{2})\pi$ , where $[x]$ denotes the greatest integer function, then $f$ is
a.
continuous for every real $x$
b.
discontinuous only at $x= 0$
c.
discontinuous only at non-zero integral values of $x$
d.
continuous only at $x= 0$
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Q63 mcq
If the lines $\frac{x-1}{2} = \frac{y+1}{3} = \frac{z-1}{4}$ and $\frac{x-3}{1} = \frac{y-k}{2} = \frac{z}{1}$ intersect, then $k$ is equal to
a.
$-1$
b.
$\frac{2}{9}$
c.
$\frac{9}{2}$
d.
$0$
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Q64 mcq
In a $\Delta PQR$ , if $3 sin P + 4 cos Q = 6$ and $4 sin Q + 3 cos P = 1$ , then the angle $R$ is equal to
a.
$\frac{5\pi}{6}$
b.
$\frac{\pi}{6}$
c.
$\frac{\pi}{4}$
d.
$\frac{3\pi}{4}$
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Q65 mcq
An equation of a plane parallel to the plane $x-2y+ 2z-5 = 0$ and at a unit distance from the origin is
a.
$x-2y+ 2z-3 = 0$
b.
$x-2y+ 2z+ 1 = 0$
c.
$x-2y+ 2z-1 = 0$
d.
$x-2y+ 2z+ 5 = 0$
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Q66 mcq
Statement $1$ : An equation of a common tangent to the parabola $y^{2} = 16\sqrt{3}x$ and the ellipse $2x^{2} +y^{2} = 4$ is $y= 2x+ 2\sqrt{3}$ . Statement $2$ : If the line $y=mx+ \frac{4\sqrt{3}}{m} , (m\neq 0)$ is a common tangent to the parabola $y^{2} = 16\sqrt{3}x$ and the ellipse $2x^{2} +y^{2} = 4$ , then $m$ satisfies $m^{4} + 2m^{2} = 24$ .
a.
Statement $1$ is false, statement $2$ is true
b.
Statement $1$ is true, statement $2$ is true; statement $2$ is a correct explanation for statement $1$
c.
Statement $1$ is true, statement $2$ is true; statement $2$ is not a correct explanation for statement $1$
d.
Statement $1$ is true, statement $2$ is false
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Q67 mcq
If $z\neq 1$ and $\frac{z^{2}}{z-1}$ is real, then the point represented by the complex number $z$ lies
a.
either on the real axis or on a circle passing through the origin
b.
on a circle with centre at the origin
c.
either on the real axis or on a circle not passing through the origin
d.
on the imaginary axis
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Q68 mcq
The area bounded between the parabolas $x^{2} = \frac{y}{4}$ and $x^{2} = 9y$ , and the straight line $y= 2$ is
a.
$20\sqrt{2}$
b.
$\frac{10\sqrt{2}}{3}$
c.
$\frac{20\sqrt{2}}{3}$
d.
$10\sqrt{2}$
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Q69 mcq
If the integral $\int \frac{5 tanx}{tanx-2}dx=x+aln | sinx-2 cosx| +k$ , then $a$ is equal to
a.
$-1$
b.
$-2$
c.
$1$
d.
$2$
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Q70 mcq
A line is drawn through the point $(1, 2)$ to meet the coordinate axes at $P$ and $Q$ such that it forms a triangle $OPQ$ , where $O$ is the origin. If the area of the triangle $OPQ$ is least, then the slope of the line $PQ$ is
a.
$-\frac{1}{4}$
b.
$-4$
c.
$-2$
d.
$- \frac{1}{2}$
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Q71 mcq
Consider the function $f(x) = |x-2| + |x-5|,x\in R$ . Statement $1$ : $f'(4) = 0$ Statement $2$ : $f$ is continuous in $[2, 5]$ , differentiable in $(2, 5)$ and $f(2) =f(5)$ .
a.
Statement $1$ is false, statement $2$ is true
b.
Statement $1$ is true, statement $2$ is true; statement $2$ is a correct explanation for statement $1$
c.
Statement $1$ is true, statement $2$ is true; statement $2$ is not a correct explanation for statement $1$
d.
Statement $1$ is true, statement $2$ is false
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Q72 mcq
If $n$ is a positive integer, then $( + 1)\sqrt{3}^{2n} -( -1)\sqrt{3}^{2n}$ is
a.
an irrational number
b.
an odd positive integer
c.
an even positive integer
d.
a rational number other than positive integers
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Q73 mcq
A spherical balloon is filled with $4500\,\pi$ cubic meters of helium gas. If a leak in the balloon causes the gas to escape at the rate of $72\,\pi$ cubic meters per minute, then the rate (in meters per minute) at which the radius of the balloon decreases $49$ minutes after the leakage began is
a.
$\frac{9}{7}$
b.
$\frac{7}{9}$
c.
$\frac{2}{9}$
d.
$\frac{9}{2}$
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Q74 mcq
Let $x_{1}, x_{2}, … … , x_{n}$ be $n$ observations, and let $-x$ be their arithematic mean and $\sigma ^{2}$ be their variance. Statement $1$ : Variance of $2x_{1}, 2x_{2}, … … , 2x_{n}$ is $4\sigma ^{2}$ . Statement $2$ : Arithmetic mean of $2x_{1}, 2x_{2}, … . . , 2x_{n}$ is $-$ . $4x$
a.
Statement $1$ is false, statement $2$ is true
b.
Statement $1$ is true, statement $2$ is true; statement $2$ is a correct explanation for statement $1$
c.
Statement $1$ is true, statement $2$ is true; statement $2$ is not a correct explanation for statement $1$
d.
Statement $1$ is true, statement $2$ is false
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Q75 mcq
If $100$ times the $100^{th\,}$ term of an $AP$ with non zero common difference equals the $50$ times its $50^{th\,}$ term, then the $150^{th\,}$ term of this $AP$ is
a.
$-150$
b.
$150$ times its $50^{th\,}$ term
c.
$150$
d.
zero
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Q76 mcq
Let $X = {1, 2, 3, 4, 5}$ . The number of different ordered pairs $(Y,Z)$ that can be formed such that $Y ⊆ X,Z$ $⊆X$ and $Y \cap Z$ is empty, is
a.
$5^{2}$
b.
$3^{5}$
c.
$2^{5}$
d.
$5^{3}$
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Q77 mcq
The negation of the statement "If I become a teacher, then I will open a school" is
a.
I will become a teacher and I will not open a school
b.
Either I will not become a teacher or I will not open a school
c.
Neither I will become a teacher nor I will open a school
d.
I will not become a teacher or I will open a school
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Q78 mcq
The length of the diameter of the circle which touches the $x$ -axis at the point $(1, 0)$ and passes through the point $(2, 3)$ is
a.
$\frac{10}{3}$
b.
$\frac{3}{5}$
c.
$\frac{6}{5}$
d.
$\frac{5}{3}$
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Q79 mcq
$--$ Let $ABCD$ be a parallelogram such that $A\vec{B}= \vec{q},A\vec{D}= \vec{p}$ and $\angle BAD$ be an acute angle. If $\vec{r}$ is the vector that coincides with the altitude directed from the vertex $B$ to the side $AD$ , then $\vec{r}$ is given by
a.
$\vec{r}= 3\vec{q}- \frac{3(\vec{p}\cdot \vec{q})}{(\vec{p}\cdot \vec{p})} \vec{p}$
b.
$\vec{r}= -\vec{q}+( \frac{\vec{p}\cdot \vec{q}}{\vec{p}\cdot \vec{p}\rightarrow \rightarrow})\vec{p}$
c.
$\vec{r}= \vec{q}- ( \frac{\vec{p}\cdot \vec{q}}{\vec{p}\cdot \vec{p}})\vec{p}$
d.
$\vec{r}= -3\vec{q}+ \frac{3(\vec{p}\cdot \vec{q})}{(p\cdot \vec{p})}\vec{p}$
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Q80 mcq
If $g(x) =\int _{0}^{x} cos 4t dt$ , then $g(x+\pi )$ equals
a.
$\frac{g(x)}{g(\pi )}$
b.
$g(x) +g(\pi )$
c.
$g(x) - g(\pi )$
d.
None of these
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Q81 mcq
Let $a,b\in R$ be such that the function $f$ given by $f(x) = ln |x| +bx^{2} +ax,x\neq 0$ has extreme values at $x= -1$ and $x= 2$ . Statement 1: $f$ has local maximum at $x= -1$ and at $x= 2$ . Statement 2: $a = \frac{1}{2}$ and $b = \frac{-1}{4}$
a.
Statement $1$ is false, statement $2$ is true
b.
Statement $1$ is true, statement $2$ is true; statement $2$ is a correct explanation for statement $1$
c.
Statement $1$ is true, statement $2$ is true; statement $2$ is not a correct explanation for statement $1$
d.
Statement $1$ is true, statement $2$ is false
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Q82 mcq
The population $p(t)$ at time $t$ of a certain mouse species satisfies the differential equation $\frac{dp(t)}{dt} = 0.5\,p(t)$ $-450$ . If $p(0) = 850$ , then the time at which the population becomes zero is
a.
$2 ln 18$
b.
$ln 9$
c.
$\frac{1}{2}ln 18$
d.
$ln 18$
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Q83 mcq
$1 0 0 1 0$ $( ) ( ) ( )$ Let $A= 2 1 0$ . If $u_{1}$ and $u_{2}$ are column matrices such that $Au_{1} = 0$ and $Au_{2} = 1$ , then $( ) ( ) ( )$ $3 2 1 0 0$ $u_{1}+u_{2}$ is equal to
a.
$-1$ $( )$ $1$ $( )$ $0$
b.
$-1$ $( )$ $1$ $( )$ $-1$
c.
$-1$ $( )$ $-1$ $( )$ $0$
d.
$1$ $( )$ $-1$ $( )$ $-1$
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Q84 mcq
Assuming the balls to be identical except for difference in colours, the number of ways in which one or more balls can be selected from $10$ white, $9$ green and $7$ black balls is
a.
$880$
b.
$629$
c.
$630$
d.
$879$
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Q85 mcq
Let $P$ and $Q$ be $3 \times 3$ matrices with $P \neq Q$ . If $P^{3} =Q^{3}$ and $P^{2}Q=Q^{2}P$ , then determinant of $(P^{2} +Q^{2})$ is equal to
a.
$-2$
b.
$1$
c.
$0$
d.
$-1$
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Q86 mcq
Let $\hat{a}$ and $\hat{b}$ be two unit vectors. If the vectors $\vec{c}= \hat{a}+ 2\hat{b}$ and $\vec{d}= 5\hat{a}-4\hat{b}$ are perpendicular to each other, then the angle between $\hat{a}$ and $\hat{b}$ is
a.
$\frac{\pi}{6}$
b.
$\frac{\pi}{2}$
c.
$\frac{\pi}{3}$
d.
$\frac{\pi}{4}$
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Q87 mcq
Statement $1$ : The sum of the series $1 + (1 + 2 + 4) + (4 + 6 + 9) + (9 + 12 + 16) + … … + (361 + 380 + 400)$ is $8000$ . Statement $2$ : $\sum ^{n}_{k=1} (k^{3}-(k-1)^{3})=n^{3}$ for any natural number $n$ .
a.
Statement $1$ is false, statement $2$ is true.
b.
Statement $1$ is true, statement $2$ is true; statement $2$ is a correct explanation for statement $1$
c.
Statement $1$ is true, statement $2$ is true; statement $2$ is not a correct explanation for statement $1$
d.
Statement $1$ is true, statement $2$ is false
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Q88 mcq
An ellipse is drawn by taking a diameter of the circle $(x-1)^{2} +y^{2} = 1$ as its semiminor axis and a diameter of the circle $x^{2} + (y-2)^{2} = 4$ as its semi-major axis. If the centre of the ellipse is the origin and its axes are the coordinate axes, then the equation of the ellipse is
a.
$4x^{2} +y^{2} = 4$
b.
$x^{2} + 4y^{2} = 8$
c.
$4x^{2} +y^{2} = 8$
d.
$x^{2} + 4y^{2} = 16$
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Q89 mcq
If the line $2x+y=k$ passes through the point which divides the line segment joining the points $(1, 1)$ and $(2, 4)$ in the ratio $3 : 2$ , then $k$ equals
a.
$\frac{29}{5}$
b.
$5$
c.
$6$
d.
$\frac{11}{5}$
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Q90 mcq
The equation $e^{sinx} - e^{-sinx} -4 = 0$ has
a.
infinite number of real roots
b.
no real roots
c.
exactly one real root
d.
exactly four real roots
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