Solved papers for WB JEE Medical WB JEE Medical Solved Paper-2014

done WB JEE Medical Solved Paper-2014

  • question_answer1) Consider three vectors \[A=\hat{i}+\hat{j}-2\hat{k},\,\]\[B=\hat{i}-\hat{j}+\hat{k}\]and \[C=2\hat{i}-3\hat{j}+4\hat{k}.\]A vector X of the form \[\alpha A+\beta B\](\[\alpha \] and\[\beta \] are numbers) is perpendicular to C. The ratio of \[\alpha \]and \[\beta \] is

    A) 1:1

    B) 2:1

    C) -1:1

    D) 3:1

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  • question_answer2) Three capacitors \[3\mu F,6\mu F\] and \[6\mu F\]are connected in series to a source of 120 V. The potential difference, in volt, across the \[3\mu F\]capacitor will be

    A) 24

    B) 30

    C) 40

    D) 60

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  • question_answer3) A galvanometer having internal resistance \[10\,\Omega \] requires 0.01 A for a full scale deflection. To convert this galvanometer to a voltmeter of full-scale deflection at 120 V, we need to connect a resistance of

    A) \[11990\,\Omega \]in series

    B) \[11990\,\Omega \]in parallel

    C) \[12010\,\Omega \] in series

    D) \[12010\,\Omega \]in parallel

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  • question_answer4) A whistle whose an column is open at both ends has a fundamental frequency of 5100 Hz. If the speed of sound in air is \[340\,m{{s}^{-1}},\] the length of the whistle, in cm, is

    A) 5/3

    B) 10/3

    C) 5

    D) 20/3

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  • question_answer5) The output Y of the logic circuit given below is

    A) \[\frac{\bar{A}+B}{(A+B)}.\bar{A}\]

    B) \[\bar{A}\]

    C) \[\overline{(\bar{A}+B)}.\bar{A}\]

    D) \[\overline{(\bar{A}+B)}.A\]

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  • question_answer6) One mole of an ideal monoatomic gas is heated at a constant pressure from \[0{{\,}^{o}}C\]to \[100{{\,}^{o}}C.\] Then the change in the internal energy of the gas is (Given,\[R=8.32\,J\,mol{{\,}^{-1}}{{K}^{-1}}\])

    A) \[0.83\times {{10}^{3}}J\]

    B) \[4.6\times {{10}^{3}}\,J\]

    C) \[2.08\times {{10}^{3}}\,J\]

    D) \[1.25\times {{10}^{3}}\,J\]

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  • question_answer7) The ionization energy of hydrogen is 13.6 eV. The energy of the photon released when an electron jumps from the first excited state \[(n=2)\] to the ground state of a hydrogen atom is

    A) 3.4eV

    B) 4.53eV

    C) 10.2eV

    D) 13.6eV

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  • question_answer8) A parallel plate capacitor is charged and then disconnected from the charging battery. If the plates are now moved farther apart by pulling at them by means of insulating handles, then

    A) the energy stored in the capacitor decreases

    B) the capacitance of the capacitor increases

    C) the charge on the capacitor decreases

    D) the voltage across the capacitor increases

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  • question_answer9) When a particle executing SHM oscillates with a frequency v, then the kinetic energy of the particle

    A) changes periodically with a frequency of v

    B) changes periodically with a frequency of 2v

    C) changes periodically with a frequency of \[v/2\]

    D) remains constant

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  • question_answer10) In which of the following pairs, the two physical quantities have different dimensions?

    A) Plancks constant and angular momentum

    B) Impulse and linear momentum

    C) Moment of inertia and moment of a force

    D) Energy and torque

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  • question_answer11) A cricket ball thrown across a field is at heights \[{{h}_{1}}\] and\[{{h}_{2}}\] from the point of projection at times \[{{t}_{1}}\] and \[{{t}_{2}}\]respectively after the throw. The ball is caught by a fielder at the same height as that of projection. The time of flight of the ball in this journey is

    A) \[\frac{{{h}_{1}}t_{2}^{2}-{{h}_{2}}_{1}^{2}}{{{h}_{1}}{{t}_{2}}-{{h}_{2}}{{t}_{1}}}\]

    B) \[\frac{{{h}_{1}}t_{1}^{2}-{{h}_{2}}_{2}^{2}}{{{h}_{2}}{{t}_{1}}-{{h}_{1}}{{t}_{2}}}\]

    C) \[\frac{{{h}_{1}}t_{2}^{2}-{{h}_{2}}_{1}^{2}}{{{h}_{1}}{{t}_{2}}-{{h}_{2}}{{t}_{1}}}\]

    D) \[\frac{{{h}_{1}}t_{1}^{2}-{{h}_{2}}_{2}^{2}}{{{h}_{1}}{{t}_{1}}-{{h}_{2}}{{t}_{2}}}\]

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  • question_answer12) A small metal sphere of radius a is falling with a velocity \[\upsilon \] through a vertical column of a viscous liquid. If the coefficient of viscosity of the liquid is \[\eta ,\]then the sphere encounters an opposing force of

    A) \[6\pi \eta {{a}^{2}}v\]

    B) \[\frac{6\eta v}{\pi a}\]

    C) \[6\pi \eta av\]

    D) \[\frac{\pi \eta v}{6{{a}^{3}}}\]

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  • question_answer13) A scientist proposes a new temperature scale in which the ice point is 25 X (X is the new unit of temperature) and the steam point is 305 X. The specific heat capacity of water in this new scale is \[(in\,J\,k{{g}^{-1}}\,{{X}^{-1}})\]

    A) \[4.2\,\,\times {{10}^{3}}\]

    B) \[3.0\,\,\times {{10}^{3}}\]

    C) \[1.2\,\,\times \,\,{{10}^{3}}\]

    D) \[1.5\,\,\times \,{{10}^{3}}\]

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  • question_answer14) One mole of a van der Waals gas obeying the equation \[\left( p+\frac{a}{{{V}^{2}}} \right)(V-b)=RT\]Undergoes the quasi-static cyclic process which is shown in the p-V diagram. The net heat absorbed by the gas in this process is

    A) \[\frac{1}{2}({{\rho }_{1}}-{{\rho }_{2}})({{V}_{1}}-{{V}_{2}})\]

    B) \[\frac{1}{2}({{\rho }_{1}}+{{\rho }_{2}})({{V}_{1}}-{{V}_{2}})\]

    C) \[\frac{1}{2}\left( {{p}_{1}}+\frac{a}{V_{1}^{2}}-{{p}_{2}}-\frac{a}{V_{2}^{2}} \right)({{V}_{1}}-{{V}_{2}})\]

    D) \[\frac{1}{2}\left( {{p}_{1}}+\frac{a}{V_{1}^{2}}+{{p}_{2}}+\frac{a}{V_{2}^{2}} \right)({{V}_{1}}-{{V}_{2}})\]

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  • question_answer15) A wooden block is floating on water kept in a beaker. 40% of the block is above the water surface. Now the beaker is kept inside a lift that starts going upward with acceleration equal to g/2. The block will then

    A) sink

    B) float with 10% above the water surface

    C) float with 40% above the water surface

    D) float with 70% above the water surface

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  • question_answer16) A smooth massless string passes over a smooth fixed pulley. Two masses \[{{m}_{1}}\]and \[{{m}_{2}},({{m}_{1}}>{{m}_{2}})\] are tied at the two ends of the string. The masses are allowed to move under gravity starting from rest. The total external force acting on the two masses is

    A) \[{{m}_{2}},({{m}_{1}}>{{m}_{2}})\]

    B) \[\frac{{{({{m}_{1}}-{{m}_{2}})}^{2}}}{{{m}_{1}}+{{m}_{2}}}g\]

    C) \[({{m}_{1}}-{{m}_{2}})g\]

    D) \[\frac{{{({{m}_{1}}+{{m}_{2}})}^{2}}}{{{m}_{1}}-{{m}_{2}}}g\]

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  • question_answer17) To determine the coefficient of friction between a rough surface and a block, the surface is kept inclined at \[{{45}^{o}}\] and the block is released from rest. The block takes a time t in moving a distance d. The rough surface is then replaced by a smooth surface and the same experiment is repeated. The block now takes a time 112 in moving down the same distance d. The coefficient of friction is

    A) 3/4

    B) 5/4

    C) 1/2

    D) \[1/\sqrt{2}\]

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  • question_answer18) A metal rod is fixed rigidly at two ends so as to prevent its thermal expansion. If \[L,\alpha \]and Y respectively denote the length of the rod, coefficient of linear thermal expansion and Youngs modulus of its material, then for an increase in temperature of the rod by \[\Delta T,\]the longitudinal stress developed in the rod is

    A)  inversely proportional to \[\alpha \]

    B)  inversely proportional to \[\gamma \]

    C)  directly proportional to \[\Delta T/\gamma \]

    D)  independent of L

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  • question_answer19) A particle is moving uniformly in a circular path of radius r. When it moves through an angular displacement \[\theta ,\] then the magnitude of the corresponding linear displacement will be

    A) \[2r\,d\cos \left( \frac{\theta }{2} \right)\]

    B) \[2r\,\cot \left( \frac{\theta }{2} \right)\]

    C) \[2r\,\tan \left( \frac{\theta }{2} \right)\]

    D) \[2r\,\sin \left( \frac{\theta }{2} \right)\]

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  • question_answer20) A uniform rod is suspended horizontally from its mid-point. A piece of metal whose weight is w is suspended at a distance \[l\] from the mid- point. Another weight \[{{W}_{1}}\]is suspended on the other side at a distance \[{{l}_{1}}\]the mid-point to bring the rod to a horizontal position. When \[\omega \]is completely immersed in water, \[{{\omega }_{1}}\]needs to be kept at a distance \[{{l}_{2}}\] from the mid-point to get the rod back into horizontal position. The specific gravity of the metal piece is

    A) \[\frac{w}{{{w}_{1}}}\]

    B) \[\frac{w{{l}_{1}}}{wl-{{w}_{1}}{{l}_{2}}}\]

    C) \[\frac{{{l}_{1}}}{{{l}_{1}}-{{l}_{2}}}\]

    D) \[\frac{{{l}_{1}}}{{{l}_{2}}}\]

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  • question_answer21) A drop of some liquid of volume \[0.04\,c{{m}^{3}}\]is placed on the surface of a glass slide. Then another glass slide is placed on it in such a way that the liquid forms a thin layer of area \[20\,c{{m}^{2}}\]between the surfaces of the two slides. To separate the slides a force of \[16\times {{10}^{5}}\]dyne has to be applied normal to the surfaces. The surface tension of the liquid is (in dyne\[-\,c{{m}^{-1}}\])

    A) 60

    B) 70

    C) 80

    D) 90

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  • question_answer22) An electron in a circular orbit of radius 0.05 nm performs \[{{10}^{16}}\] revolutions per second. The magnetic moment due to this rotation of electron is \[(in\,A{{m}^{2}})\]

    A) \[2.16\times {{10}^{-23}}\]

    B) \[3.21\times {{10}^{-22}}\]

    C) \[3.21\times {{10}^{-24}}\]

    D) \[1.26\times {{10}^{-23}}\]

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  • question_answer23) A very small circular loop of radius a is initially (at\[t=0\]) coplanar and concentric with a much larger fixed circular loop of radius b. A constant current \[I\] flows in the larger loop. The smaller loop is rotated with a constant angular speed\[\omega \]about the common diameter. The emf induced in the smaller loop as a function of time t is

    A) \[\frac{\pi {{a}^{2}}{{\mu }_{0}}l}{2b}\omega \cos \,(\omega t)\]

    B) \[\frac{\pi {{a}^{2}}{{\mu }_{0}}l}{2b}\omega \sin \,({{\omega }^{2}}{{t}^{2}})\]

    C) \[\frac{\pi {{a}^{2}}{{\mu }_{0}}l}{2b}\omega \sin \,(\omega t)\]

    D) \[\frac{\pi {{a}^{2}}{{\mu }_{0}}l}{2b}\omega {{\sin }^{2}}\,(\omega t)\]

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  • question_answer24) A luminous object is separated from a screen by distance d. A convex lens is placed between the object and the screen such that it forms a distinct image on the screen. The maximum possible focal length of this convex lens is

    A) \[4d\]

    B) \[2d\]

    C) \[\frac{d}{2}\]

    D) \[\frac{d}{4}\]

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  • question_answer25) An infinite sheet carrying a uniform surface charge density \[\sigma \] lies on the \[xy-\]plane. The work done to carry a charge q from the point \[A=a(\hat{i}+2\hat{j}+3\hat{k})\]to the point \[A=a(\hat{i}+2\hat{j}+3\hat{k})\](where a is a constant with the dimension of length and \[{{\varepsilon }_{0}}\]is the permittivity of free space) is

    A) \[\frac{3\sigma aq}{2{{\varepsilon }_{0}}}\]

    B) \[\frac{2\sigma aq}{{{\varepsilon }_{0}}}\]

    C) \[\frac{5\sigma aq}{2{{\varepsilon }_{0}}}\]

    D) \[\frac{3\sigma aq}{{{\varepsilon }_{0}}}\]

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  • question_answer26) The intensity of magnetization of a bar magnet is \[5.0\times {{10}^{4}}A{{m}^{-1}}.\] The magnetic length and the area of cross-section of the magnet are 12 cm and \[1\text{ }c{{m}^{2}}\]respectively. The magnitude of magnetic moment of this bar magnet is (in SI unit)

    A) 0.6

    B) 1.3

    C) 1.24

    D) 2.4

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  • question_answer27) A particle moves with constant acceleration along a straight line starting from rest. The percentage increase in its displacement during the 4th second compared to that in the 3rd second is

    A) 33%

    B) 40%

    C) 66%

    D) 77%

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  • question_answer28) A proton of mass m and charge q is moving in a plane with kinetic energy E. If there exists a uniform magnetic field B, perpendicular to the plane of the motion, the proton will move in a circular path of radius

    A) \[\frac{2Em}{qB}\]

    B) \[\frac{\sqrt{2Em}}{qB}\]

    C) \[\frac{\sqrt{Em}}{2qB}\]

    D) \[\frac{\sqrt{2Eq}}{mB}\]

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  • question_answer29) An artificial satellite moves in a circular orbit around the earth. Total energy of the satellite is given by E. The potential energy of the satellite is

    A) \[-2E\]

    B) \[2E\]

    C) \[\frac{2E}{3}\]

    D) \[-\frac{2E}{3}\]

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  • question_answer30) In which of the following phenomena, the heat waves travel along straight lines with the speed of light?

    A) Thermal conduction

    B) Forced convection

    C) Natural convection

    D) Thermal radiation

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  • question_answer31) In the bandgap between valence band and conduction band in a material is 5.0 eV, then the material is

    A) semiconductor

    B) good conductor

    C) superconductor

    D) insulator

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  • question_answer32) A uniform solid spherical ball is rolling down a smooth inclined plane from a height \[h.\]The velocity attained by the ball when it reaches the bottom of the inclined plane is \[\upsilon .\]If the ball is now thrown vertically upwards with the same velocity \[\upsilon ,\]the maximum height to which the ball will rise is

    A) \[\frac{5h}{8}\]

    B) \[\frac{3h}{5}\]

    C) \[\frac{5h}{7}\]

    D) \[\frac{7h}{9}\]

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  • question_answer33) Two coherent monochromatic beams of intensities \[I\]and \[4I\] respectively are superposed. The maximum and minimum intensities in the resulting pattern are

    A) \[5l\]and\[3l\]

    B) \[9l\] and\[3l\]

    C) \[4l\] and\[l\]

    D) \[9l\]and\[l\]

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  • question_answer34) In the circuit shown assume the diode to be ideal. When \[{{V}_{i}}\]increases from 2V to 6 V, the change in the current is (in mA)

    A) zero

    B) 20

    C) \[80/3\]

    D) 40

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  • question_answer35) If n denotes a positive integer, h the Plancks constant, q the charge and B the magnetic field, then the quantity \[\left[ \frac{nh}{2\pi qB} \right]\] has the dimension of

    A) area

    B) length

    C) speed

    D) acceleration

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  • question_answer36) In a transistor output characteristics commonly used in common emitter configuration, the base current \[{{I}_{B}},\]the collector current \[{{I}_{C}}\] and the collector-emittes voltage\[{{V}_{CE}}\] have values of the following orders of magnitude in the active region

    A) \[{{l}_{B}}\]and\[{{l}_{C}}\]both are in \[\mu A\]and \[{{V}_{CE}}\]in volt

    B) \[{{l}_{B}}\]is in \[\mu A\]and\[{{l}_{C}}\] is in mA and \[{{V}_{CE}}\]in volt

    C) \[{{l}_{B}}\]is in mA and \[{{l}_{C}}\] is in \[{{l}_{C}}\]and \[{{V}_{CE}}\]in volt

    D) \[{{l}_{B}}\] is in mA and \[{{l}_{C}}\]is in mA and\[{{V}_{CE}}\] in mV

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  • question_answer37) The displacement of a particle in a periodic motion is given by \[y=4{{\cos }^{2}}\left( \frac{t}{2} \right)\sin (1000t).\]This displacement may be considered as the result of superposition of\[n\]independent harmonic oscillations. Here \[n\] is

    A) 1

    B) 2

    C) 3

    D) 4

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  • question_answer38) Consider a black body radiation in a cubical box at absolute temperature T. If the length of each side of the box is doubled and the temperature of the walls of the box and that of the radiation is halved, then the total energy

    A) halves

    B) doubles

    C) quadruples

    D) remains the same

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  • question_answer39) Consider two concentric spherical metal shells of radii \[{{r}_{1}}\] and \[{{r}_{2}}({{r}_{2}}>{{r}_{1}}).\]If the outer shell has a charge q and the inner one is grounded, the charge on the inner shell is

    A) \[\frac{-{{r}_{2}}}{{{r}_{1}}}q\]

    B) zero

    C) \[\frac{-{{r}_{1}}}{{{r}_{2}}}q\]

    D) \[-q\]

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  • question_answer40) Four cells, each of emf E and internal resistance r, are connected in series across an external resistance R. By mistake one of the cells is connected in reverse. Then the current in the external circuit is

    A) \[\frac{2E}{4r+R}\]

    B) \[\frac{3E}{4r+R}\]

    C) \[\frac{3E}{3r+R}\]

    D) \[\frac{2E}{3r+R}\]

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  • question_answer41) Same quantity of ice is filled in each of the two metal containers P and Q having the same size, shape and wall thickness but made of different materials. The containers are kept in identical surroundings. The ice in P melts completely in time \[{{t}_{1}}\]whereas in Q takes a time \[{{t}_{2}}.\]The ratio of thermal conductivities of the materials of P and Q is

    A) \[{{t}_{2}}:{{t}_{1}}\]

    B) \[{{t}_{1}}:{{t}_{2}}\]

    C) \[t_{1}^{2}:t_{2}^{2}\]

    D) \[t_{2}^{2}:t_{1}^{2}\]

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  • question_answer42) For the radioactive nuclei that undergo either \[\alpha \]or\[\beta \] decay, which one of the following cannot occur?

    A) Isobar of original nucleus is produced

    B) Isotope of the original nucleus is produced

    C) Nuclei with higher atomic number than that of the original nucleus is produced

    D) Nuclei with lower atomic number than that of the original nucleus is produced

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  • question_answer43) A car is moving with a speed of \[72\,km-{{h}^{-1}}\]towards a roadside source that emits sound at a frequency of 850 Hz. The car driver listens to the sound while approaching the source and again while moving away from the source after crossing it. If the velocity of sound is \[340\,m{{s}^{-1}},\] the difference of the two frequencies, the driver hears is

    A) 50 Hz

    B) 85 Hz

    C) 100 Hz

    D) 150 Hz

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  • question_answer44) The energy of gamma \[(\gamma )\] ray photon is \[{{E}_{\gamma }}\]and that of an X-ray photon is \[{{E}_{x}}.\]If the visible light photon has an energy of \[{{E}_{\upsilon }},\] then we can say that

    A) \[{{E}_{x}}{{E}_{\gamma }}{{E}_{v}}\]

    B) \[{{E}_{\gamma }}>{{E}_{v}}>{{E}_{x}}\]

    C) \[{{E}_{\gamma }}>{{E}_{x}}>{{E}_{v}}\]

    D) \[{{E}_{x}}>{{E}_{v}}>{{E}_{\gamma }}\]

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  • question_answer45) The intermediate image formed by the objective of a compound microscope is

    A) real, inverted and magnified

    B) real, erect and magnified

    C) virtual, erect and magnified

    D) virtual, inverted and magnified

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  • question_answer46) A solid uniform sphere resting on a rough horizontal plane is given a horizontal impulse directed through its centre so that it starts sliding with an initial velocity \[{{\upsilon }_{0}}.\]When it finally starts rolling without slipping the speed of its centre is

    A) \[\frac{2}{7}{{v}_{0}}\]

    B) \[\frac{3}{7}{{v}_{0}}\]

    C) \[\frac{5}{7}{{v}_{0}}\]

    D) \[\frac{6}{7}{{v}_{0}}\]

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  • question_answer47) The de-Broglie wavelength of an electron is the same as that of a \[\text{50}\,\text{ke}\,\text{V}\]X-ray photon. The ratio of the energy of the photon to the kinetic energy of the electron is (the energy equivalent of electron mass is 0.5 MeV)

    A) 1 : 50

    B) 1 : 20

    C) 20 :1

    D) 50 : 1

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  • question_answer48) A glass slab consists of thin uniform layers of progressively decreasing refractive indices \[\text{RI}\] (see figure) such that the \[\text{RI}\]of any layer is \[\mu -m\,\Delta \mu .\]Here, \[\mu \]and \[\Delta \mu \]denote the \[\text{RI}\]of 0th layer and the difference in RI between any two consecutive layers, respectively. The integer \[m=0,1,2,3,...\]denotes the numbers of the successive layers. A ray of light from the 0th layer enters the 1st layer at an angle of incidence of \[{{30}^{o}}.\] After undergoing the \[mth\]refraction, the ray emerges parallel to the interface. If \[\mu =1.5\]and \[\Delta \mu =0.015,\]the value of\[m\]is

    A) 20

    B) 30

    C) 40

    D) 50

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  • question_answer49) A long conducting wire carrying a current I is bent at 120? (see figure). The magnetic field B at a point P on the right bisector of bending angle at a distance d from the bend is (\[{{\mu }_{0}}\] is the permeability of free space)

    A) \[\frac{3{{\mu }_{0}}l}{2\pi d}\]

    B) \[\frac{{{\mu }_{0}}l}{2\pi d}\]

    C) \[\frac{{{\mu }_{0}}l}{\sqrt{3}\pi d}\]

    D) \[\frac{\sqrt{3}{{\mu }_{0}}l}{2\pi d}\]

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  • question_answer50) A circuit consists of three batteries of emf \[{{E}_{1}}=1\,V,{{E}_{2}}=2\,V\]and \[{{E}_{3}}=3\,V\]and internal resistances \[1\,\Omega ,\,2\,\Omega \] and\[1\,\Omega \]respectively which are connected in parallel as shown in the figure. The potential difference between points P and Q is

    A) 1.0 V

    B) 2.0 V

    C) 2.2 V

    D) 3.0 V

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  • question_answer51) Sound waves are passing through two routes-one in straight path and the other along a semicircular path of radius r and are again combined into one pipe and superposed as shown in the figure. If the velocity of sound waves in the pipe is \[\upsilon ,\]then frequencies of resultant waves of maximum amplitude will be integral multiples of

    A) \[\frac{v}{r(\pi -2)}\]

    B) \[\frac{v}{r(\pi -1)}\]

    C) \[\frac{2v}{r(\pi -1)}\]

    D) \[\frac{v}{r(\pi +1)}\]

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  • question_answer52) To determine the composition of a bimetallic alloy, a sample is first weighed in air and then in water. These weights are found to be \[{{\omega }_{1}}\]and \[{{\omega }_{2}}\]respectively. If the densities of the two constituents metals are \[{{\rho }_{1}}\]and \[{{\rho }_{2}}\]respectively, then the weight of the first metal in the sample is (where \[{{\rho }_{\omega }}\]is the density of water)

    A) \[\frac{{{\rho }_{1}}}{{{\rho }_{w}}({{\rho }_{2}}-{{\rho }_{1}})}[{{w}_{1}}({{\rho }_{2}}-{{\rho }_{w}})-{{w}_{2}}{{\rho }_{2}}]\]

    B) \[\frac{{{\rho }_{1}}}{{{\rho }_{w}}({{\rho }_{2}}+{{\rho }_{1}})}[{{w}_{1}}({{\rho }_{2}}-{{\rho }_{w}})+{{w}_{2}}{{\rho }_{2}}]\]

    C) \[\frac{{{\rho }_{1}}}{{{\rho }_{w}}({{\rho }_{2}}-{{\rho }_{1}})}[{{w}_{1}}({{\rho }_{2}}+{{\rho }_{w}})-{{w}_{2}}{{\rho }_{1}}]\]

    D) \[\frac{{{\rho }_{1}}}{{{\rho }_{w}}({{\rho }_{2}}-{{\rho }_{1}})}[{{w}_{1}}({{\rho }_{2}}-{{\rho }_{w}})-{{w}_{2}}{{\rho }_{1}}]\]

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  • question_answer53) A 10 W electric heater is used to heat a container filled with 0.5 kg of water. It is found that the temperature of water and the container rises by \[{{3}^{o}}K\]in 15 min. The container is then emptied, dried and filled with 2 kg of oil. The Same heater now raises the temperature of container-oil system by \[{{2}^{o}}K\]in 20 min. Assuming that there is no heat loss in the process and the specific heat of water is \[4200\,J\,k{{g}^{-1}}{{K}^{-1}},\] the specific heat of oil in the same unit is equal to

    A) \[1.50\,\,\times \,\,{{10}^{3}}\]

    B) \[2.55\,\,\times \,\,{{10}^{3}}\]

    C) \[3.00\,\,\times \,\,{{10}^{3}}\]

    D) \[5.10\,\,\times \,\,{{10}^{3}}\]

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  • question_answer54) An object is placed 30 cm away from a convex lens of focal length 10 cm and a sharp image is formed on a screen. Now a concave lens is placed in contact with the convex lens. The screen now has to be moved by 45 cm to get a sharp image again. The magnitude of focal length of the concave lens is (in cm)

    A) 72

    B) 60

    C) 36

    D) 20

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  • question_answer55) Three identical square plates rotate about the axes shown in the figure in such a way that their kinetic energies are equal. Each of the rotation axes passes through the centre of the square. Then the ratio of angular speeds\[{{\omega }_{1}}:{{\omega }_{2}}:{{\omega }_{3}}\]is

    A) \[1:1:1\]

    B) \[\sqrt{2}:\sqrt{2}:1\]

    C) \[1:\sqrt{2}:1\]

    D) \[1:2:\sqrt{2}\]

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  • question_answer56) A heating element of resistance r is fitted inside an adiabatic cylinder which carries a frictionless piston of mass m and cross-section A as shown in diagram. The cylinder contains one mole of an ideal diatomic gas. The current flows through the element such that the temperatures rises with time t as \[\Delta t=\alpha t+\frac{1}{2}\beta {{t}^{2}}\] (\[\alpha \]and\[\beta \]are constants), while pressure remains constant. The atmospheric pressure above the piston is \[{{P}_{0}}.\]Then

    A) the rate of increase in internal energy is\[\frac{5}{2}R(\alpha +\beta t)\]

    B) the current flowing in the element is \[\sqrt{\frac{5}{2r}R(\alpha +\beta t)}\]

    C) the piston moves upwards with constant acceleration

    D) the piston moves upwards with constant speed

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  • question_answer57) A thin rod AB is held horizontally so that it can freely rotate in a vertical plane about the end A as shown in the figure. The potential energy of the rod when it hangs vertically is taken to be zero. The end B of the rod is released from rest from a horizontal position. At the instant the rod makes an angle \[\theta \] with the horizontal

    A) the speed of end B is proportional to \[\sqrt{\sin \theta }\]

    B) the potential energy is proportional to \[(1-cos\,\theta )\]

    C) the angular acceleration is proportional to \[cos\,\theta \]

    D) the torque about A remains the same as its initial value

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  • question_answer58) Find the correct statement(s) about photoelectric effect.

    A) There is no significant time delay between the absorption of a suitable radiation and the emission of electrons

    B) Einstein analysis gives a threshold frequency above which no electron can be emitted

    C) The maximum kinetic energy of the emitted photoelectrons is proportional to the frequency of incident radiation

    D) The maximum kinetic energy of electrons does not depend on the intensity of radiation

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  • question_answer59) Half of the space between the plates of a parallel-plate capacitor is filled with a dielectric material of dielectric constant K. The remaining half contains air as shown in the figure. The capacitor is now given a charge Q. Then

    A) electric field in the dielectric-filled region is higher than that in the air-filled region

    B) on the two halves of the bottom plate the charge densities are unequal

    C) charge on the half of the top plate above the air-filled part is\[\frac{Q}{K+1}\]

    D) capacitance of the capacitor shown above is\[(1+K)\frac{{{C}_{0}}}{2},\]where \[{{C}_{0}}\]is the capacitance of the same capacitor with the dielectric removed.

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  • question_answer60) A stream of electrons and protons are directed towards a narrow slit in a screen (see figure). The intervening region has a uniform electric field E (vertically downwards) and a uniform magnetic field B (out of the plane of the figure) as shown. Then

    A) electrons and protons with speed \[\frac{|E|}{|B|}\]will pass through the slit

    B) protons with speed \[|E|/|B|\] will pass through the slit, electrons of the same speed will not

    C) neither electrons nor protons will go through the slit irrespective of their speed

    D) electrons will always be deflected upwards irrespective of their speed

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  • question_answer61) The emission spectrum of hydrogen discovered first and the region of the electromagnetic spectrum in which it belongs, respectively are

    A) Lyman, ultraviolet

    B) Lyman, visible

    C) Balmer, ultraviolet

    D) Balmer, visible

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  • question_answer62) The electronic configuration of Cu is

    A) \[\text{ }\!\![\!\!\text{ }Me\text{ }\!\!]\!\!\text{ }3{{s}^{2}},3{{p}^{6}},3{{d}^{9}},4{{s}^{2}}\]

    B) \[\text{ }\!\![\!\!\text{ N}e\text{ }\!\!]\!\!\text{ }3{{s}^{2}},3{{p}^{6}},3{{d}^{10}},4{{s}^{1}}\]

    C) \[\text{ }\!\![\!\!\text{ N}e\text{ }\!\!]\!\!\text{ }3{{s}^{2}},3{{p}^{6}},3{{d}^{3}},4{{s}^{2}},4{{p}^{6}}\]

    D) \[\text{ }\!\![\!\!\text{ N}e\text{ }\!\!]\!\!\text{ }3{{s}^{2}},3{{p}^{6}},3{{d}^{5}},4{{s}^{2}},4{{p}^{4}}\]

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  • question_answer63) As per de-Broglies formula a macroscopic particle of mass 100 g and moving at a velocity of \[100\,cm\,{{s}^{-1}}\] will have a wavelength of

    A) \[6.6\times {{10}^{-29}}cm\]

    B) \[6.6\times {{10}^{-30}}cm\]

    C) \[6.6\times {{10}^{-31}}cm\]

    D) \[6.6\times {{10}^{-32}}cm\]

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  • question_answer64) For one mole of an ideal gas, the slope of \[V\upsilon s.\]T curve at constant pressure of 2 aim is \[X\,L\,mo{{l}^{-1}}\,{{K}^{-1}}.\]The value of the ideal universal gas constant R in terms of X is

    A) \[X\text{ }L\text{ }atm\text{ }mo{{l}^{-1}}{{K}^{-1}}\]

    B) \[\frac{X}{2}\text{ }L\text{ }atm\text{ }mo{{l}^{-1}}{{K}^{-1}}\]

    C) \[2X\text{ }L\text{ }atm\text{ }mo{{l}^{-1}}{{K}^{-1}}\]

    D) \[2X\,atm\,{{L}^{-1}}\,mo{{l}^{-1}}{{K}^{-1}}\]

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  • question_answer65) At a certain temperature the time required for the complete diffusion of 200 mL of \[{{H}_{2}}\]gas is 30min. The time required for the complete diffusion of 50 mL of \[{{O}_{2}}\]gas at the same temperature will be

    A) 60 min

    B) 30 min

    C) 45 min

    D) 15min

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  • question_answer66) The IUPAC name of the following molecule is

    A) 5, 6-dimethylhept-2-ene

    B) 2, 3-dimethylhept-5-ene

    C) 5, 6-dimethylhept-3-ene

    D) 5-iso-propylhex-2-ene

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  • question_answer67) The reagents to carry out the following conversion are

    A) \[HgS{{O}_{4}}/dil.{{H}_{2}}S{{O}_{4}}\]

    B) \[B{{H}_{3}};{{H}_{2}}{{O}_{2}}/NaOH\]

    C) \[Os{{O}_{4}};HI{{O}_{4}}\]

    D) \[NaN{{H}_{2}}/C{{H}_{3}}l;HgS{{O}_{4}}/dil.{{H}_{2}}S{{O}_{4}}\]

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  • question_answer68) The correct order of decreasing H-C-H angle in the following molecule is

    A) I > II > III

    B) II > I > III

    C) III > II > I

    D) I > III > II

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  • question_answer69) During the emission of a positron from a nucleus, the mass number of the daughter element remains the same but the atomic number

    A) is decreased by 1 unit

    B) is decreased by 2 units

    C) is increased by 1 unit

    D) remains unchanged

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  • question_answer70) \[\beta -\]emission is always accompanied by

    A) formation of antineutrino and \[\alpha -\]particle

    B) emission of \[\alpha -\]particle and \[\gamma -\]ray

    C) formation of antineutrino and \[\gamma -\]ray

    D) formation of antineutrino and positron

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  • question_answer71) Four gases P, Q, R and S have almost same values of b but their a values (a, b are van der Waals constants) are in the order Q R < S < P. At a particular temperature, among the four gases, the most easily liquefiable one is

    A) P

    B) 0

    C) R

    D) S

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  • question_answer72) Among the following structures the one which is not a resonating structure of others is (I) (II) (III) (IV)

    A) I

    B) II

    C) III

    D) IV

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  • question_answer73) The compound that will have a permanent dipole moment among the following is





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  • question_answer74) The correct order of decreasing length of the bond as indicated by the arrow in the following structures is

    A) I > II > III

    B) II > I > III

    C) III > II > I

    D) I > III > II

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  • question_answer75) An atomic nucleus having low n/p ratio tries to find stability by

    A) the emission of an a-particle

    B) the emission of a positron

    C) capturing an orbital electron (K-electron capture)

    D) emission of a p-particle

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  • question_answer76) \[({{\,}_{32}}G{{e}^{76}}{{,}_{34}}S{{e}^{76}})\]and \[({{\,}_{14}}S{{i}^{30}}{{,}_{16}}{{S}^{32}})\] are examples of

    A) isotopes and isobars

    B) isobars and isotones

    C) isotones and isotopes

    D) isobars and isotopes

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  • question_answer77) \[_{98}C{{f}^{246}}\]was formed along with a neutron when an unknown radioactive substance was bombarded with \[{{\,}_{6}}{{C}^{12}}.\]The unknown substance was

    A) \[{{\,}_{91}}P{{a}^{234}}\]

    B) \[{{\,}_{90}}T{{h}^{234}}\]

    C) \[{{\,}_{92}}{{U}^{235}}\]

    D) \[{{\,}_{92}}{{U}^{238}}\]

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  • question_answer78) The rate of a certain reaction is given by, rate \[=k{{[{{H}^{+}}]}^{n}}.\] The rate increases 100 times when the pH changes from 3 to 1. The order \[(n)\] of the reaction is

    A) 2

    B) 0

    C) 1

    D) 1.5

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  • question_answer79) The values of \[\Delta H\]and \[\Delta S\]of a certain reaction are  \[-400\,kJ\,mo{{l}^{-1}}\]  and  \[-20\,kJ\,mo{{l}^{-1}}{{K}^{-1}}\] respectively. The temperature below which the reaction is spontaneous, is

    A)  100 K  

    B) \[20{{\,}^{o}}C\]  

    C)  20 K  

    D) \[120{{\,}^{o}}C\]

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  • question_answer80) The correct statement regarding the following compounds is

    A) all three compounds are chiral

    B) only I and II are chiral

    C) I and III are diastereomers

    D) only I and III are chiral

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  • question_answer81) The correct statement regarding the following energy diagrams is

    A) Reaction M is faster and less exothermic than reaction N

    B) Reaction M is slower and less exothermic than reaction N

    C) Reaction M is faster and more exothermic than reaction N

    D) Reaction M is slower and more exothermic than reaction N

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  • question_answer82) In the following reaction, the product E is \[\underset{CHO}{\overset{CHO}{\mathop{|}}}\,\xrightarrow[(ii)\,{{H}^{+}}]{(i)\,NaOH}E\]

    A) \[\underset{CHO}{\mathop{\underset{|}{\mathop{C{{H}_{2}}OH}}\,}}\,\]

    B) \[\underset{C{{O}_{2}}H}{\overset{CHO}{\mathop{|}}}\,\]

    C) \[\underset{C{{O}_{2}}H}{\overset{C{{H}_{2}}OH}{\mathop{|}}}\,\]

    D) \[\underset{C{{O}_{2}}H}{\overset{C{{O}_{2}}H}{\mathop{|}}}\,\]

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  • question_answer83) If \[C{{l}_{2}}\]is passed through hot aqueous NaOH, the products formed have Cl in different oxidation states. These are indicated as

    A) \[-1\]and\[+1\]

    B) \[-1\] and\[+5\]

    C) \[+\,1\]and \[+\,5\]

    D) \[-1\] and \[+\,3\]

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  • question_answer84) Commercial sample of \[{{H}_{2}}{{O}_{2}}\]is labeled as \[10\,V.\] Its % strength is nearly

    A) 3

    B) 6

    C) 9

    D) 12

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  • question_answer85) The enthalpy of vaporisation of a certain liquid at its boiling point of \[35{{\,}^{o}}C\]is \[24.64\,kJ\,mo{{l}^{-1}}.\] The value of change in entropy for the process is

    A) \[704\,J{{K}^{-1}}\,mo{{l}^{-1}}\]

    B) \[80\,J{{K}^{-1}}\,mo{{l}^{-1}}\]

    C) \[24.64\,J{{K}^{-1}}mo{{l}^{-1}}\]

    D) \[7.04\,J{{K}^{-1}}\,mo{{l}^{-1}}\]

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  • question_answer86) Given that \[C+{{O}_{2}}\xrightarrow{{}}C{{O}_{2}};\Delta {{H }^{o}}=-x\,kJax\] \[2CO+{{O}_{2}}\xrightarrow{{}}2C{{O}_{2}};\Delta {{H}^{o}}=-y\,kJ\] The heat of formation of carbon monoxide will be

    A)  \[\frac{y-2x}{2}\]

    B)  \[y+2x\]

    C)  \[2x-y\]

    D)  \[\frac{2x-y}{2}\]

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  • question_answer87) The intermediate J in the following Wittig reaction is





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  • question_answer88) Among the following compounds, the one(s) that gives (give) effervescence with aqueous \[NaHC{{O}_{3}}\]solution is (are) \[\underset{\text{I}}{\mathop{{{\text{(C}{{\text{H}}_{\text{3}}}\text{CO)}}_{\text{2}}}\text{O}}}\,\,\,\underset{\text{II}}{\mathop{\,\,\text{C}{{\text{H}}_{\text{3}}}\text{COOH}\,\,\,\underset{\text{III}}{\mathop{\text{PhOH}}}\,\,\,}}\,\,\underset{\text{IV}}{\mathop{\text{C}{{\text{H}}_{\text{3}}}\text{COCHO}}}\,\]

    A) I and II

    B) I and III

    C) Only II

    D) I and IV

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  • question_answer89) The 4th higher homologue of ethane is

    A) butane

    B) pentane

    C) hexane

    D) heptane

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  • question_answer90) In case of heteronuclear diatomics of the type AB, where A is more electronegative than B, bonding molecular orbital resembles the character of A more than that of B. The statement

    A) is false

    B) is true

    C) cannot be evaluated since data is not sufficient

    D) is true only for certain systems

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  • question_answer91) The hydrides of the first elements in groups 15-17, namely\[N{{H}_{3}},{{H}_{2}}O\]and HF respectively show abnormally high values for melting and boiling points. This is due to

    A) small size of N, O and F

    B) the ability to form extensive intermolecular H-bonding

    C) the ability to form extensive intramolecular H-bonding

    D) effective van der Waals interaction

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  • question_answer92) The quantity of electricity needed to separately electrolyze 1 M solution of \[ZnS{{O}_{4}},AlC{{l}_{3}}\]and \[AgN{{O}_{3}}\]completely is in the ratio of

    A) 2 : 3 : 1

    B) 2 : 1 : 1

    C) 2 : 1 : 3

    D) 2 : 2 : 1

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  • question_answer93) The amount of electrolytes required to coagulate a given amount of \[AgI\]colloidal solution (-ve charge) will be in the order

    A) \[NaN{{O}_{3}}>A{{l}_{2}}{{(N{{O}_{3}})}_{3}}>Ba{{(N{{O}_{3}})}_{2}}\]

    B) \[A{{l}_{2}}{{(N{{O}_{3}})}_{3}}>Ba{{(N{{O}_{3}})}_{2}}>NaN{{O}_{3}}\]

    C) \[A{{l}_{2}}{{(N{{O}_{3}})}_{3}}>NaN{{O}_{3}}>Ba{{(N{{O}_{3}})}_{2}}\]

    D) \[NaN{{O}_{3}}>Ba{{(N{{O}_{3}})}_{2}}>A{{l}_{2}}{{(N{{O}_{3}})}_{3}}\]

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  • question_answer94) The value of \[\Delta H\]for cooling 2 mole of an ideal monoatomic gas from \[225{{\,}^{o}}C\]to \[125{{\,}^{o}}C\]at constant pressure will be [given \[{{C}_{p}}=\frac{5}{2}R\]]

    A) 250 R

    B) \[-500\,R\]

    C) \[500\,R\]

    D) \[-250\,R\]

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  • question_answer95) An amine \[{{C}_{3}}{{H}_{9}}N\]reacts with benzene sulphonyl chloride to form a white precipitate which is insoluble in aq. NaOH. The amine is





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  • question_answer96) The number of amino acids and number of peptide bonds in a linear tetrapeptide (made of different amino acids) are respectively

    A) 4 and 4

    B) 5 and 5

    C) 5 and 4

    D) 4 and 3

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  • question_answer97) Among the following, the one which is not a greenhouse gas, is

    A) \[N{{O}_{2}}\]

    B) \[C{{O}_{2}}\]

    C) \[C{{H}_{4}}\]

    D) \[{{O}_{2}}\]

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  • question_answer98) The \[\text{pH}\]of \[{{10}^{-4}}\,\text{M}\,\text{KOH}\]solution will be

    A) 4

    B) 11

    C) 10.5

    D) 10

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  • question_answer99) The system that contains the maximum number of atoms is

    A) \[4.25\text{ }g\text{ of }N{{H}_{3}}\]

    B) \[8\,g\,\text{of}\,{{\text{O}}_{2}}\]

    C) \[2g\,\text{of}\,{{H}_{2}}\]

    D) \[4\text{ }g\,\text{of }He\]

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  • question_answer100) Among the following observations, the correct one that differentiates between \[SO_{3}^{2-}\]and \[SO_{4}^{2-}\]is

    A) both form precipitate with \[BaC{{l}_{2}},SO_{3}^{2-}\]dissolves in HCI but \[SO_{4}^{2-}\]does not

    B) \[SO_{3}^{2-}\]forms precipitate with \[BaC{{l}_{2}},SO_{4}^{2-}\]does not

    C) \[SO_{4}^{2-}\]forms precipitate with \[BaC{{l}_{2}},SO_{3}^{2-}\]does not

    D) both form precipitate with \[BaC{{l}_{2}},SO_{4}^{2-}\]dissolves in \[HCl\] but \[SO_{3}^{2-}\]does not

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  • question_answer101) Metal ion responsible for the Minimata disease is

    A) \[C{{o}^{2+}}\]

    B) \[H{{g}^{2+}}\]

    C) \[C{{u}^{2+}}\]

    D) \[Z{{n}^{2+}}\]

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  • question_answer102) The reagent with which the following reaction is best accomplished is

    A) \[{{H}_{3}}P{{O}_{2}}\]

    B) \[{{H}_{3}}P{{O}_{3}}\]

    C) \[{{H}_{3}}P{{O}_{4}}\]

    D) \[NaHS{{O}_{3}}\]

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  • question_answer103) In DNA, the consecutive deoxynucleotides are connected \[\upsilon ia\]

    A) phosphodiester linkage

    B) phosphomonoester linkage

    C) phosphotriester linkage

    D) amide linkage

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  • question_answer104) The reaction of aniline with chloroform under alkaline conditions leads to the formation of

    A) phenylcyanide

    B) phenylisonitrile

    C) phenylcyanate

    D) phenylisocyanate

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  • question_answer105) The two half-cell reactions of an electrochemical cell is given as \[A{{g}^{+}}+{{e}^{-}}\xrightarrow{{}}Ag;\] \[E_{A{{g}^{+}}/Ag}^{o}=-0.3995\,V\] \[F{{e}^{2+}}\xrightarrow{{}}F{{e}^{3+}}+{{e}^{-}};E_{F{{e}^{3+}}/F{{e}^{2+}}}^{o}=-0.7120\,V\] The value of cell EMF will be

    A) \[-\,0.3125\,\text{V}\]

    B) \[0.3125\,\text{V}\]

    C) \[1.114\,\text{V}\]

    D) \[-\,1.114\text{V}\]

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  • question_answer106) The compressibility factor (Z) of one mole of a van der Waals gas of negligible a value is

    A) 1

    B) \[\frac{bp}{RT}\]

    C) \[1+\frac{bp}{RT}\]

    D) \[1-\frac{bp}{RT}\]

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  • question_answer107) When phenol is treated with \[{{D}_{2}}S{{O}_{4}}/{{D}_{2}}O.\]some of the hydrogens get exchanged. The final product in this exchange reaction is





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  • question_answer108) The most likely protonation site in the following molecule is

    A) \[C-1\]

    B) \[C-2\]

    C) \[C-3\]

    D) \[C-4\]

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  • question_answer109) The order of decreasing ease of abstraction of hydrogen atoms in the following molecule

    A) \[{{H}_{a}}>{{H}_{b}}>{{H}_{c}}\]

    B) \[{{H}_{a}}>{{H}_{c}}>{{H}_{b}}\]

    C) \[{{H}_{b}}>{{H}_{a}}>{{H}_{c}}\]

    D) \[{{H}_{c}}>{{H}_{b}}>{{H}_{a}}\]

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  • question_answer110) At \[25{{\,}^{o}}C,\] the molar conductance of 0.007 M hydrofluoric acid is 150 mho \[\text{c}{{\text{m}}^{\text{2}}}\,\text{mo}{{\text{l}}^{-1}}\]and its \[A_{m}^{o}=500\,\,\text{mho}\,\text{c}{{\text{m}}^{2}}\text{mo}{{\text{l}}^{-1}}.\]The value of the dissociation constant of the acid at the given concentration at \[25{{\,}^{o}}C\]is

    A) \[7\times {{10}^{-4}}M\]

    B) \[7\times {{10}^{-5}}M\]

    C) \[9\times {{10}^{-3}}M\]

    D) \[9\times {{10}^{-4}}M\]

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  • question_answer111) To observe an elevation of boiling point of \[0.05{{\,}^{o}}C,\] the amount of a solute (mol. wt. = 100) to be added to 100 g of water \[({{K}_{b}}=0.5)\] is

    A) 2 g

    B) 0.5 g

    C) 1 g

    D) 0.75 g

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  • question_answer112) The volume of ethyl alcohol (density 1.15 g/cc) that has to be added to prepare 100 cc of 0.5 M ethyl alcohol solution in water is

    A) 1.15 cc

    B) 2 cc

    C) 2.15 cc

    D) 2.30 cc

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  • question_answer113) The bond angle in\[\text{N}{{\text{H}}_{3}}({{107.2}^{o}}).\]is smaller than \[\text{N}{{\text{H}}_{3}}({{107.2}^{o}}).\]This is because of

    A) large size of F compared to H

    B) large size of N compared to F

    C) opposite polarity of N in the two molecules

    D) small size of H compared to N

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  • question_answer114) A piece of wood from an archaeological sample has 5.0 counts \[{{\min }^{-1}}\]per gram of \[C-14,\]while a fresh sample of wood has a count of \[15.0\,{{\min }^{-1}}{{g}^{-1}}.\] If half-life of C-14 is 5770 yr, the age of the archaeological sample is

    A) 8,500 yr

    B) 9,200 yr

    C) 10,000 yr

    D) 11. 000 yr

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  • question_answer115) The structure of \[\text{Xe}{{\text{F}}_{\text{6}}}\]is experimentally determined to be distorted octahedron. Its structure according to VSEPR theory is

    A) octahedron

    B) trigonal bipyramid

    C) pentagonal bipyramid

    D) tetragonal bipyramid

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  • question_answer116) Two gases X (molecular weight\[{{M}_{X}}\]) and Y (molecular weight\[{{M}_{Y}}:{{M}_{Y}}:{{M}_{X}}\]) are at the same temperature T in two different containers. Their root mean square velocities are \[{{C}_{X}}\]and \[{{C}_{Y}}\]respectively. If the average kinetic energies per molecule of two gases X and \[Y\] are \[{{E}_{X}}\]and \[{{E}_{Y}}\]respectively then which of the following relation(s) is(are) true?

    A) \[{{E}_{X}}>{{E}_{Y}}\]

    B) \[{{C}_{X}}>{{C}_{Y}}\]

    C) \[{{E}_{X}}={{E}_{Y}}=(3/2)RT\]

    D) \[{{E}_{X}}={{E}_{Y}}=(3/2){{k}_{B}}T\]

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  • question_answer117) For a spontaneous process, the correct statement(s) is (are)

    A) \[{{(\Delta {{G}_{system}})}_{T,p}}>0\]

    B) \[(\Delta {{S}_{system}})+(\Delta {{S}_{surroundings}})>0\]

    C) \[{{(\Delta {{G}_{system}})}_{T,p}}<0\]

    D) \[{{(\Delta {{U}_{system}})}_{T,V}}>0\]

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  • question_answer118) The formal potential of \[F{{e}^{3+}}/F{{e}^{2+}}\]in a sulphuric acid and phosphoric acid mixture \[({{E}^{o}}=+\,0.61\text{V})\,\] is much lower than the standard potential \[({{E}^{o}}=+0.77\,V).\] This is due to

    A) formation of the species \[{{[FeHP{{O}_{4}}]}^{+}}\]

    B) lowering of potential upon complexation

    C) formation of the species \[{{[FeS{{O}_{4}}]}^{+}}\]

    D) high acidity of the medium

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  • question_answer119) Cupric compounds are more stable their cuprous counterparts in solid state. This is because

    A) The endothermic character of the 2nd IP c not so high

    B) size of \[C{{u}^{2+}}\]is less than \[C{{u}^{+}}\]

    C) \[C{{u}^{2+}}\] has stabler electronic configuration as compared to \[C{{u}^{+}}\]

    D) the lattice energy released for cupric compounds is much higher than \[C{{u}^{+}}\]

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  • question_answer120) Among the following statements about the molecules X and Y, the one(s) which correct is (are)

    A) X and Y are diastereomers

    B) X and Y are enantiomers

    C) X and Y are both aldohexoses

    D) X is a D-sugar and Y is an L-sugar

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  • question_answer121) One molecule of triglyceride is produced using

    A) one fatty acid and one glycerol

    B) one fatty acid and three glycerols

    C) three fatty acids and three glycerois

    D) three fatty acids and one glycerol

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  • question_answer122) Glutenin is an important protein in

    A) potato

    B) wheat

    C) soyabean

    D) spinach

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  • question_answer123) Which one of the following is enriched with a non-reducing sugar?

    A) Grapes

    B) Germinating barley grains

    C) Table sugar

    D) Mothers milk

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  • question_answer124) Select the correct statement related to mitosis.

    A) Amount of DNA in the parent cell is first halved and then distributed into two daughter cells

    B) Amount of DNA in the parent cell is first doubled and then distributed into two daughter cells

    C) Amount of DNA in the parent cell is first halved and then distributed into four daughter cells

    D) Amount of DNA in the parent cell is first doubled and then distributed into four daughter cells

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  • question_answer125) The frequency of crossing-over occurring between two genes located on the same chromosome depends on

    A) length of the chromosome

    B) position of the centromere

    C) activities of two genes

    D) distance between two genes

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  • question_answer126) Chlorophyll molecules are located in the

    A) thylakoid membrane

    B) thylakoid lumen

    C) stroma

    D) inner chloroplast membrane

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  • question_answer127) The primary cell wall is mainly made up of

    A) lignin

    B) pectin

    C) cellulose

    D) protein

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  • question_answer128) Which of the following statements is wrong for sucrose?

    A) It is a disaccharide

    B) It is a non-reducing sugar

    C) It accumulates in the cytoplasm

    D) It is comprised of maltose and fructose

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  • question_answer129) Which of the following is always absent in prokaryotic cells?

    A) Ribosome

    B) Mitochondria

    C) DNA

    D) Cell wall

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  • question_answer130) Which of the following tissues provide maximum mechanical support to plant organs?

    A) Sclerenchyma

    B) Collenchyma

    C) Parenchyma

    D) Aerenchyma

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  • question_answer131) The Respiratory Quotient (RQ) of glucose is

    A) 0.5

    B) 0.7

    C) 1.0

    D) 1.5

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  • question_answer132) Cross-pollination through insect agent is called

    A) anthropophily

    B) malacophily

    C) entemophily

    D) ornithophily

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  • question_answer133) Cleistogamous flowers are

    A) bisexual flowers which remain opened

    B) bisexual flowers which remain closed

    C) open female flower

    D) open mate flower

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  • question_answer134) Which one of the following is a growth regulator produced by plants?

    A) Naphthalene acetic acid

    B) Zeatin

    C) 2,4-dichlorophenoxy acetic acid

    D) Benzyl aminopurine

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  • question_answer135) In apple, the edible portion is

    A) mesocarp

    B) epicarp

    C) endocarp

    D) thalamus

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  • question_answer136) Anish is having colour blindness and married to Sheela, who is not colourblind. What is the chance that their son will have the disease?

    A) 100%

    B) 50%

    C) 25%

    D) 0%

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  • question_answer137) Insect pest resistant Bt cotton plant was developed using

    A) somaclonal variation

    B) micropropagation

    C) somatic hybridisation

    D) Transgenic technology

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  • question_answer138) In which one of the following, expenditure of energy is required?

    A) Osmosis

    B) Diffusion

    C) Active transport

    D) Passive transport

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  • question_answer139) Emasculation ensures cross-pollination in

    A) staminate flower

    B) bisexual flower

    C) neuter flower

    D) pistillate flower

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  • question_answer140) The protein component of a holoenzyme is known as

    A) coenzyme

    B) cofactor

    C) prosthetic group

    D) apoenzyme

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  • question_answer141) Pseudopodia are produced by

    A) plasma cell

    B) mast cell

    C) adipose cell

    D) fibroblast cell

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  • question_answer142) Formation ofpolysome does not require

    A) rRNA

    B) mRNA

    C) tRNA

    D) snRNA

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  • question_answer143) \[{{K}_{m}}\]is

    A) product

    B) enzyme

    C) constant

    D) unit

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  • question_answer144) Proteins helping in kinetocore formation of yeast are

    A) \[CBF2\]and\[Ka{{r}^{3}}\text{ }P\]

    B) \[CBF2\]and \[CBF3\]

    C) \[CBF3\]and \[Ka{{r}^{3}}\text{ }P\]

    D) \[CBF2,\text{ }CBF3\]and \[Ka{{r}^{3}}\text{ }P\]

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  • question_answer145) Juvenile hormone in insect is released from

    A) protocerebrum

    B) corpora cardiaca

    C) corpora allata

    D) thoracic gland

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  • question_answer146) Genes which are located only in th X-chromosome are known as

    A) epistasis genes

    B) holandric genes

    C) operator genes

    D) antiepistasis genes

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  • question_answer147) Industrial melanism is an

    A) effect of industrial pollution

    B) effect of mutation

    C) evidence of survival of fittest

    D) evidence of favour of natural selection

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  • question_answer148) The concept of hot-spot was first introduced by

    A) Mayer

    B) Simpson

    C) Myers

    D) David

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  • question_answer149) With the rise of water temperature, dissolvec oxygen

    A) remains unchanged

    B) increases in amount

    C) decreases in amount

    D) is more available to the aquatic organisms

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  • question_answer150) Intermediate host of malarial parasite is

    A) pig

    B) man

    C) mosquito

    D) larva of mosquito

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  • question_answer151) Which codon is not an indicator of completion of protein synthesis?

    A) UAG

    B) AUG

    C) UAA

    D) UGA

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  • question_answer152) Kyoto Protocol is a multination international treaty for

    A) phasing out green house gases

    B) controlling ozone destroying substances

    C) management of hazardous wastes

    D) conservation of biodiversity

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  • question_answer153) The objective ofRamsar Convention was

    A) forest conservation

    B) wildlife conservation

    C) wetland conservation

    D) biodiversity conservation

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  • question_answer154) Which of the following human parasites require mosquito to complete their life-cycle?

    A) Ascaris lumbricoides and Wucherena bancrofti

    B) Leishmania donovani and Plasmodium ovale

    C) Ascaris lumbricoides and Leishmania donovani

    D) Wuchereria bancrofti and Plasmodium ovale

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  • question_answer155) In which diagnostic system, piezoelectric effect and reverse piezoelectric effect are involved?

    A) EEG

    B) CAT

    C) USG

    D) MRI

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  • question_answer156) Main cause of eutrophication is

    A) fluctuation of temperature

    B) unusual growth of aquatic vegetations

    C) enrichment of nutrients

    D) abundance of microorganisms

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  • question_answer157) The body ofRohu fish is covered by

    A) cycloid scale, but the tail of homocercal

    B) placoid scale, but the tail of heterocercal

    C) cycloid scale, but the tail of heterocercal

    D) ptecoid scale, but the tail is homocercal

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  • question_answer158) Management of National Park is controlled by

    A) State Government

    B) Central Government

    C) United Nations

    D) Non-Government Organisations

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  • question_answer159) Which one is an example of living fossil?

    A) Coral

    B) Ascidia

    C) Octopus

    D) King crab

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  • question_answer160) The removal of Keystone species will affect the

    A) producers

    B) consumers

    C) ecosystem

    D) decomposers

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  • question_answer161) Objects less than \[0.2\,\mu m\]in size cannot be seen under light microscope because

    A) the wave length of visible light is \[3900-7800\text{ }\overset{\text{o}}{\mathop{\text{A}}}\,\]

    B) only two types of lenses are used

    C) maximum magnifying power of ocular lens is 20 X

    D) maximum magnifying power of objective lens is 100 X

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  • question_answer162) If the sequence of bases in the coding strand of a double-stranded DNA is 5-GTTCGAGTC-3, the sequence of bases in its transcript will be

    A) 5-GACUCGAAC-3


    C) 5-GUUCGAGUC-3


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  • question_answer163) Immunity that develops in the foetus after receiving antibodies from mothers blood through placenta is

    A) naturally acquired active immunity

    B) artificially acquired active immunity

    C) naidrally acquired passive immunity

    D) artificially acquired passive immunity

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  • question_answer164) The serous membrane which covers the lungs is called

    A) pericardium

    B) peritoneum

    C) perichondrium

    D) pleura

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  • question_answer165) The volume of air that can be breathed in by maximum forced inspiration over and above the normal inspiration is called

    A) expiratory reserved volume

    B) inspiratory reserved volume

    C) vital capacity

    D) inspiratory capacity

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  • question_answer166) How many ATP are produced when one molecule of \[\text{FAD}{{\text{H}}_{\text{2}}}\]is oxidised to FAD through electron transport system?

    A) 2

    B) 3

    C) 1

    D) 4

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  • question_answer167) Which valve is present at the opening of coronary sinus?

    A) Mitral valve

    B) Eustachian valve

    C) Thebesian valve

    D) Tricaspid valve

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  • question_answer168) Which of the following organs does not produce any digestive enzymes?

    A) Salivary gland

    B) Pancreas

    C) Liver

    D) Stomach

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  • question_answer169) The disease that occurs in mature adult human being due to deficiency of calciferol is

    A) keratomalacia

    B) osteomalacia

    C) glossitis

    D) pernicious anaemia

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  • question_answer170) Which blood cells can engulf bacteria b; phagocytosis?

    A) Eosinophil and basophil

    B) Basophil and lymphocyte

    C) Neutrophil and monocyte

    D) Neutrophil and lymphocyte

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  • question_answer171) Which excitatory neurotransmitter is involved in the transmission of impulse at th neuromuscular junction?

    A) Epinephrine

    B) Serotonin

    C) Acetylcholine

    D) Glycine

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  • question_answer172) Which area of cerebral cortex is responsible for the interpretation of speech?

    A) Brocas area

    B) Wernickes area

    C) Premotor area

    D) Association area of sensory cortex

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  • question_answer173) Which of the following pituitary hormones is secreted without the involvement of a Releasing Hormone (RH)?

    A) Thyroid Stimulating Hormone (TSH)

    B) Follicle Stimulating Hormone (FSH)

    C) Oxytocin

    D) Prolactin

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  • question_answer174) Which of the following hormones is a derivative of fatty acid?

    A) Gastrin

    B) Thyroxin

    C) Estrogen

    D) Prostaglandins

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  • question_answer175) Which of the following is not involved in muscular contraction?

    A) Calcium ion

    B) Troponin

    C) Actin

    D) Magnesium ion

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  • question_answer176) Proximal convoluted tubule of nephron is responsible for

    A) filtration of blood

    B) maintenance of glomerular filtration rate

    C) selective reabsorption of glucose, amino acid NaCI and water

    D) reabsorption of salts only

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  • question_answer177) Which of the following processes was discovered by Lederberg and Tatum (1946)?

    A) Transduction

    B) Transformation

    C) Asexual reproduction

    D) Conjugation

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  • question_answer178) The component of bacteria that retains the crystal violet stain during Gram staining is

    A) O-antigen

    B) Hpopolysaccharide

    C) peptidoglycan

    D) cytoplasmic membrane

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  • question_answer179) Which of the following bacteria is observed as chain-like formation?

    A) Escherichia coli

    B) Bacillus subtilis

    C) Streptococcus pyogenes

    D) Micrococcus ffavus

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  • question_answer180) During gene cloning, the enzyme used to join the insert DNA with the plasmid vector is

    A) DNA ligase

    B) restriction endonuclease

    C) alkaline phosphatase

    D) exonuclease

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  • question_answer181) The partial floral formula of a flower is \[{{\text{K}}_{(5)}}{{C}_{5}}{{A}_{(\infty )}}{{\underline{G}}_{(5)}}.\] Which of the following set of information is conveyed here?

    A) Gamosepalous, polypetalous, syncarpous and superior ovary

    B) Polysepalous, polypetalous, syncarpous and inferior ovary

    C) Gamosepalous, gamopetalous, polycarpous and superior ovary

    D) Gamosepalous, polypetalous, syncarpous and inferior ovary

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  • question_answer182) In a plant species, flower colour yellow is dominant oyer white and fruit shape round is dominant over elongated. Crossing was performed between two pure lines-one having yellow-flower and round-fruit and another with white-flower and elongated-fruit. About 20 plants survived in \[{{F}_{1}}\]progeny. Plants of Fi were allowed to self-fertilise and about 960 plants survived in \[{{F}_{2}}.\]If the traits follow Mendelian inheritance, the number of plants would have yellow-flower and round-fruit in \[{{F}_{1}}\]and \[{{F}_{2}}\]are respectively

    A) 20, 960

    B) 20. 540

    C) 10, 180

    D) 10. 60

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  • question_answer183) Match the items in column I with those in column II and choose the correct answer.

    Column I Column II
    A. Control of weeds 1. Gibberellin.
    B. Induction of germination 2. Cytokines
    C. Ripening of fruit 3. 2,4-D
    D. Delaying of senescence 4. Ethylene

    A) A-2 B-4 C-3 D-1

    B) A-3 B-1 C-4 D-2

    C) A-1 B-2 C-4 D-3

    D) A-2 B-3 C-1 D-4

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  • question_answer184) Out of 38 molecules of ATP produced upon aerobic respiration of glucose, the break up if ATP production in glycolysis (P), pyruvate to acetyl Co-A formation (Q) and Krebs cycle (R) is as follows

    A) \[P=2,Q=6,R=30\]

    B) \[P=8,Q=6,R=24\]

    C) \[P=8,Q=10,\text{ }R=20\]

    D) \[P=2,Q=12,\text{ }R=24\]

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  • question_answer185) The correct sequence of organelles in which glycolate and glyoxylate are produced sequentially in photorespiration, is

    A) chloroplast and mitochondria

    B) chloroplast and peroxisome

    C) peroxisome and mitochondria

    D) peroxisome and chioroplast

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  • question_answer186) Cells die at the time of release of secretory meterials in

    A) holocrine gland

    B) apocrine gland

    C) merocrine gland

    D) mixed or apocrine gland

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  • question_answer187) X-ray is needed for

    A) Ultrasonography

    B) CT scanning

    C) MRI

    D) NMR

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  • question_answer188) Which of the following statements is wrong?

    A) Test tube baby grows inside test tube.

    B) Test tube baby grows within mothers womb

    C) Test tube baby grows within surrogate mothers womb

    D) Test tube baby grows following uterine fertilisation

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  • question_answer189) The correct sequence of embryonic development is

    A) Blastula-Morula-Zygote-Gastrula- Embryo

    B) Zygote-Blastula-Morula-Gastrula-Embryo

    C) Zygote-Morula-Blastula-Gastrula- Embryo

    D) Gastrula-Morula-Zygote-Blastula- Embryo

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  • question_answer190) The time interval of appearance of fever in the malarial patients depends on the types of malaria. The research evidences suggest that such time intervals are-(1) 36-48 hours, (2) 48 hours and (3) 72 hours. If any such patient experiences fever at an interval of 48 hours, then the said patient suffers from

    A) only benign tertian malaria

    B) quarantan malaria or mild tertian malaria

    C) malignant tertian malaria or benign tertian malaria

    D) mild tertian malaria or benign tertian malaria

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  • question_answer191) The structure of E. coli chromosomal DNA is

    A) double-stranded, right handed and circular

    B) single-stranded, right handed and circular

    C) double-stranded, left handed and linear

    D) double-stranded, left handed and circular

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  • question_answer192) Absorption of vitamin\[-{{B}_{12}}\] in human requires T glycoprotein secreted from Q. The correct choices of P and Q are

    A) P - Extrinsic factor and Q - Stomach

    B) P - Intrinsic factor and Q - Stomach

    C) P - Intrinsic factor and Q - Small intes

    D) P- Exopolysaccharide and Q-Smail intestin

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  • question_answer193) What type of cartilaginous tissue is foul the inter-vertebral discs?

    A) Costal cartilage

    B) Hyaline cartilage

    C) White fibrous cartilage

    D) Yellow elastic cartilage

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  • question_answer194) If spermatogenesis proceeds too rap inhibin is released. Inhibin reduces the sec setion of

    A) Luteinising Hormone (LH)

    B) Follicle Stimulating Hormone (FSH)

    C) Testosterone

    D) Interstitial Cell Stimulating Hormone (ICSH)

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  • question_answer195) Which of the following statements are tru Motor cortex?

    I. It is located in the frontal lobe of cerebral cortex.
    II. It contains pyramidal cells.
    III. It is responsible for all visual function.
    IV. It is essential for our thought process.
    V. It stimulates wakefulness.
    VI. It regulates voluntary muscular movements.

    A) I, II, III and V

    B) II, III. IV and V

    C) II, IV, V and VI

    D) I, II, IV and VI

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  • question_answer196) Identify the correct statement(s) in relation to \[{{C}_{4}}\] photosynthesis

    A) Kranz anatomy is an essential feature for \[{{C}_{4}}\]plants

    B) \[{{C}_{4}}\]plants have higher water use efficiency than plants

    C) Photorespiration can be minimised when \[{{C}_{4}}\] pathway is in operation

    D) Conversion of oxaloacetate to malate occurs in the bundle sheath cells

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  • question_answer197) Genetically improved crop varieties can be developed in laboratory by

    A) somatic hybridisation

    B) transgenic technology

    C) cell suspension culture

    D) somaclonal variation

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  • question_answer198) Sand flies play significant role in spreading kala-azar because they

    A) suck blood only from the patients suffering from kala-azar

    B) convert amastigote into promastigote

    C) . engulf amastigote at the time of blood sucking from the infected persons

    D) inject promastigote into the body of non-infected persons at the time of blood sucking

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  • question_answer199) Which of the following factor(s) increase blood pressure?

    A) Increase of cardiac output

    B) Constriction of blood vessel

    C) Activation of parasympathetic nerve

    D) Increase of blood volume

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  • question_answer200) Which of the following statement(s) are true?

    A) Antibiotics can kill bacteria, but disinfectants do not

    B) Disinfectants have better bactericidal efficiency than antibiotics

    C) Antibiotics are of microbial origin, but disinfectants are chemical compounds

    D) Antibiotics can be injected into the patients, whereas disinfectants are not

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