UPSEE - Physics -2007 Unsolved Paper

• 1. UPSEE PAST PAPERSPHYSICS - UNSOLVED PAPER - 2007

2. SECTION I Straight Objective Type This section contains multiple choice questions numbered 100. Each question has 4 choices (A), (B), (C)and (D), out of which ONLY ONE is correct. 3. 01 Problem A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to a. x2 b. ex c. x d. loge x 4. 02 Problem A ball is thrown from a point with a speed v0 at an angle of projection . From the same point and at the same instant, a person starts running with a constant speed to catch the ball. Will the person be able to catch the ball ? If Yes, what should be the angle of projection ? a. Yes, 600 b. Yes, 300 c. No d. Yes, 450 5. 03 Problem Spherical balls of radius R are falling in a viscous fluid of viscosity with a velocity v. The retarding viscous force acting on the spherical ball is a. Directly proportional to R but inversely proportional to v b. Directly proportional to both radius R and velocity v c. Inversely proportional to both radius R and velocity v d. Inversely proportional to R but directly proportional to velocity v 6. 04 Problem Nickel shows ferromagnetic property at room temperature. If the temperature is increased beyond Curie temperature. Then it will show a. Para magnetism b. Anti-ferromagnetism c. No magnetic property d. Diamagnetism 7. 05 Problem In radioactive decay process, the negatively charge emitted -particles are a. The electrons present inside the nucleus b. The electrons produced as a result of the decay of neutrons inside thenucleus c. The electrons produced as a result of collision between atoms d. The electrons orbiting around the nucleus 8. 06 Problem A small coin is resting on the bottom of a beaker filled with a liquid. A ray of light from the coin travels upto the surface of the liquid and moves along its surface (see figure). How fast is the light traveling in the liquid ? a. 1.8 x 108 m/s b. 2.4 x 108 m/s c. 3.0 x 108 m/s d. 1.2 x 108 m/s 9. 07 Problem What is the value of inductance L for which the current is a maximum in a series LCR circuit with C =10 F and = 1000 s-1 ? a. 100 mH b. 1 m H c. cannot be calculated unless R is known d. 10 mH 10. 08 Problem The point charges +q, -2q and +q are placed at a point {x = 0, y = a, Z = 0}, {x = 0,y = 0,z = 0} and {x = a, y = 0, z = 0}, respectively the magnitude and direction of the electric dipole movement vector of this charge assembly are a. 2 qa along +y direction b. qa along the line joining points (x = 0, y = 0, z = 0) and (x = a, y = a, z = 0) c. 2 qa along the line joining points (x = 0, y = 0, z = 0) and (x = a, y = a, z = 0) d. 2 qa along +x direction 11. 09 Problem A nucleus A X has mass represented by M{A,Z} if Mp and M n denotes the massZ of proton and neutron respectively and BE the binding energy (in M e V), then a. BE = [M(A, Z) ZMP (A - Z)Mn]C2 b. BE = [ZMp + (A - Z)Mn M(A, Z)]C2 c. BE = [ZMp + AMn M (A, Z)]C2 d. BE = M (A, Z) ZMp (A - Z)Mn 12. 10 Problem The following figure shows a logic gate circuit with two inputs A,B and the output C. the voltage waveforms of A, B and C are as show below The logic circuit gate is a. AND gate b. NAND gate c. NOR gate d. OR gate 13. 11 Problem Assuming the sum to have a spherical outer surface if radius r, radiating like a black body at temperature toC , the power received by a unit surface, { normal to the incider rays} at a distance R from the center of the sun is a. 4 r 2 t2 4 Rr 2 (t 273)4 b.4 R216 2 r 2 t 4 c. R2 d. r 2 (t 273)4 R2 Where is the stefans constant, 14. 12 Problem The temperature of the two outer surfaces of a composite of thermal conductivity K and 2K and thickness x and 4x, respectively are T2 and T1 (T2 > T1). The rate of heat transfer through the slab, in a steady state is A T2 T1 K f, with fx equals to a. 1 b. 1/2 c. 2/3 d. 1/3 15. 13 Problem The maximum number of possible interference maximum for slit-separation equals to twice the wavelength in youngs double-site experiments, is a. Infinite b. Five c. Three d. Zero 16. 14 Problem Two spherical conductors B and C having equal radii and carrying equal charges in them repel each other with a force F when kept apart at some distance, a third spherical conductor having same radius as that of B but un charged, is brought in contact with the C and finally removed away from both, the new force of repulsion between B and C is a. F/34 b. 3F/4 c. F/8 d. 3F/8 17. 15 Problem In gamma ray emission from a nucleus a. Both the neutron number and the proton number change b. There is no change in the proton number c. Only the neuron number charges d. Only the proton number charges 18. 16 Problem A particle starting from the origin (0,0) moves in a straight line in the (x,y) plane, its Coordinates at a later time are ( 3 , 3). The path of the particle makes with the x-axis an angle of a. 300 b. 600 c. 450 d. 00 19. 17 Problem a wheel has angular acceleration of 3.0 rad/ s2 and an initial angular speed of 2.00 rad/s. in a time of 2s it has rotated through an angle { in radian }of a. 6 b. 10 c. 12 d. 4 20. 18 Problem The resistance of an ammeter is 13 and its scale is graduated for a current upto 100 A after an additional shunt has been connected to this ammeter it becomes possible to measure current upto 750 A by this meter, value of shunt resistance is a. 20 b. 2 c. 0.2 d. 2 K 21. 19 Problem under the influence of a uniform magnetic field a charged particle is moving in a circle of radius R with constant speed v. the time period of the motion a. depends on v and not on R b. depends on both R and v c. is depends of both R and v d. Depends on Rand not on v 22. 20 Problem The primary and secondary coils of a transformer have 50 and 1500 turns respectively , if the magnetic flux linked with the primary coil is given by =0+4T, where is in weber, t is time in second and 0 is a constant, the ouput voltage across the secondary coil is a. 90 V b. 120 V c. 220 V d. 30 V 23. 21 Problem Two condensers, one of capacity C and the other of capacity C/2, are connected to a V volt battery, as shown. The work done in charging fully both the condensers is a. 2CV2 b. 1/4CV2 c. 3/4CV2 d. 1/2 CV2 24. 22 Problem A uniform rod AB of length l and mass m is free to rotate about point A. the rod is released from rest in the horizontal position. Given that the moment of inertia of the rod about A is ml2/3, the initial angular acceleration of the rod will be a. 2g3l l b. mg 2 c. 3g2l d. 3gl2 25. 23 Problem The frequency of a light wave in a material is 2 x 104 Hz and wavelength is 5000 . The refractive index of material will be a. 1.40 b. 1.50 c. 3.00 d. 1.33 26. 24 Problem In the energy band diagram of a material shown below, the open circles and filled circle denote holes and electrons respectively. The material is a/an a. p-type semiconductor b. insulator c. metal d. n-type semiconductor 27. 25 Problem A car moves from X to Y with a uniform speed vu and returns to Y with a uniform speed vd. The average speed for this round trip is a.2vdvuv d vu b. v uv d c.v d vuv d vu d. vu vd2 28. 26 Problem A particle executes simple harmonic oscillation with an amplitude a. The period of oscillation is T. The minimum time taken by the particle to travel half of the amplitude from the equilibrium position is a. T/2 b. T/8 c. T/12 d. 1/2 29. 27 Problem A 5 W source emits monochromatic light of wavelength 5000 . When placed 0.5 m away, it liberates photoelectrons from a photosensitive metallic surface. When the source is moved to a distance of 1,0 m, the number of photoelectrons liberated will be reduced by a factor of a. 4 b. 8 c. 16 d. 2 30. 28 Problem A block B is pushed momentarily along a horizontal surface with an initial velocity v. If is the coefficient of sliding friction between B and the surface, block B will come to rest after a timev a.g b. gvg c.v d. vg 31. 29 Problem Two radioactive substance A and B have decay constants 5and respectively. At t = 0 they have the same number of nuclei. The ratio of number 2 1 of nuclei of A to those of e B will be after a time interval a. 14 b. 2 1 c.2 d. 4 32. 30 Problem A hollow cylinder has a charge q coulomb within it. If is the electric flux in unit of voltmeter associated with the curved surface B, the flux linked with the plane surface A in unit of voltmeter will be a. 1 q 2 0q b. 2 0 c. 3q d. 0 33. 31 Problem A transformer is used to light a 100 W and 110 V lamp from a 220 V mains. If the main current is 0.5 A, the efficiency of the transformer is approximately a. 30% b. 50% c. 90% d. 10% 34. 32 Problem A charged particle (charge q) is moving in a circle of radius R with uniform speed v. The associated magnetic moment is given by a. qvR 2 2 b. qvR2 c. qvR2 d. qvR 35. 33 Problem A particle of mass m moves in the XY plane with a velocity v along the straight line AB. If the angular momentum of the particle with respect to origin O is LA when it is at A and LB when it is at B, then a. LA > LB b. LA = LB c. The relationship between LA and LB depends upon the slope of the line AB d. LA < LB 36. 34 Problem A steady current of 1.5 A flows through a copper voltmeter for 10 min. If the electrochemical equivalent of copper is 30 x 10-5 g C-1, the mass of copper deposited on the electrode will be a. 0.40 g b. 0.50 g c. 0.67 g d. 0.27 g 37. 35 Problem In a mass spectrometer used for measuring the masses of ions, the ions are initially accelerated by an electric potential V and then made to describe semicircular paths of radius R using a magnetic field B. If V and B are kept constant, the ratio charge on the ion will be proportional to mass of the ion a. 1/R b. 1/R2 c. R2 d. R 38. 36 Problem Three resistances P, Q, R each of 2 and an unknown resistances S from the four arms of a Wheat stones bridge circuit. When a resistance of 6 is connected in parallel to S the bridge gets balanced. What is the value of S ? a. 2 b. 3 c. 6 d. 1 39. 37 Problem A mass of 2.0 kg is put on a flat pan attached to a vertical spring fixed on the ground as shown in the figure. The mass of the spring and the pan is negligible. When pressed slightly and released the mass executes a simple harmonic motion. The spring constant is 200 N/n. What should be the minimum amplitude of the motion, so that the mass gets detached from the pan ? (Take g = 10 m/s2) a. 8.0 cm b. 10.0 cm c. Any value less than 12.0 cm d. 4.0 cm 40. 38 Problem Two satellites of earth, S1 and S2, are moving in the same orbit. The mass of S1 is four times the mass of S2. Which one of the following statements is true ? a. The time period of S1 is four times that of S2 b. The potential energies of earth and satellite in the two cases are equal c. S1 and S2 are moving with the same speed d. The kinetic energies of the two satellites are equal 41. 39 Problem Charges + q and q are placed at points A and B respectively which are a distance 2L apart, C is the midpoint between A and B. The work done in moving a charge + Q along the semicircle CRD is a. qQ 4 0 LqQ b. 2 0 L qQ c.6 0 LqQ d. 6 0 L 42. 40 Problem A beam of electrons passes undeflected through mutually perpendicular electric and magnetic fields. If the electric field is switched off, and the same magnetic field is maintained, the electrons move a. In an elliptical orbit b. In a circular orbit c. Along a parabolic path d. Along a straight line 43. 41 Problem Monochromatic light of frequency 6.0 x 1014 Hz is produced by a laser. The power emitted is 2 x 10-3 W. the number of photons emitted, on the average, by the source per second is a. 5 x 1015 b. 5 x 1016 c. 5 x 1017 d. 5 x 1014 44. 42 Problem The length of a magnet is large compared to its width and breadth. The time period of its oscillation in a vibration magnetometer is 2 s. The magnet is cut along its length into three equal parts and three parts are then placed on each other with their like poles together. The time period of this combination will be a. 2 s b. 2/3 s c. 2 3 s d. 2/ 3 s 45. 43 Problem The diagram shows the energy levels for an electron in a certain atom. Which transition Show represents the emission of a photon with the most energy ? a. III b. IV c. I d. II 46. 44 Problem In the circuit, the galvanometer G shows zero deflection. If the batteries A and B have negligible internal resistance, the value of the resistor R will be a. 200 b. 100 c. 500 d. 1000 47. 45 Problem When an unpolarized light of intensity I0 is incident on a polarizing sheet, the intensity of the light which does not get transmitted is1 a. I02 b. 1 I04 c. zero d. I0 48. 46 Problem When two tuning forks (fork 1 and fork 2) are sounded simultaneously, 4 beats per second are heard. Now, some tape is attached on the prong of the fork 2. When the tuning forks are sounded again, 6 beats per second are heard. If the frequency of fork 1 is 200 Hz, then what was the original frequency of fork ? a. 200 Hz b. 202 Hz c. 196 Hz d. 204 Hz 49. 47 Problem An observer moves towards a stationary source of sound, with a velocity one- fifth of the velocity of sound. What is the percentage increase in the apparent frequency ? a. Zero b. 0.5% c. 5% d. 20% 50. 48 Problem A coil of inductance 300 mH and resistance 2 is connected to a source of voltage 2V. the current reaches helf of its State value in a. 0.05s b. 0.1 c. 0.15s d. 0.3s 51. 49 Problem The refractive index of is 1.520 for red light and 1.525m for red light let D1 and D2 be angles of minimum deviation for red and blue light respectively in as prism of this glass. Then a. D1D2 52. 50 Problem A particle of mass 100 g is thrown vertically upwards with a speed of 5 m/s. the work done by the force of gravity during the time the particle goes up is a. -0.5J b. -1.25J c. 1.25J d. 0.5J 53. 51 Problem A mass of M kg is suspended by a weightless string. The horizontal force that is required to displace w it until the string makes an le of 450 with the intale the vertical direction is a. Mg ( 2 +1) b. Mg 2 c. Mg( 2 - 1) d. Mg2 54. 52 Problem A force of F acts on o, the origin of the coordinate system .the torque about the point (1,-1)is a. F( i j) b. - F( ) i j c. F ( )i j d. - F ( ) i j 55. 53 Problem If MO is the mass of an oxygen isotope 8O17 , Mp and Mn are the masses of a proton and binding energy of the isotope is An electric charge 10 - 3 C is placed at the origin (0, 0) of x-y coordinate sys tem two points A and B are situated at ( 2 , 2 ) and (2, 0) respectively. the potential difference between the points A and B will be a. 9v b. Zero c. 2v d. 4.5 v 56. 54 Problem An electric charge 10 - 3 C is placed at the origin (0, 0) of x-y coordinate sys tem two points A and B are situated at ( 2 , 2 ) and (2, 0) respectively. the potential difference between the points A and B will be a. 9v b. Zero c. 2v d. 4.5 v 57. 55 Problem A sound absorber attenuates the sound level by 20 db .the intensity decreases by a factor of a. 1000 b. 10000 c. 10 d. 100 58. 56 Problem A circular disc of radius R is removed from a bigger circular disc of radius 2R such that the circumference of the discs coincide. the centre of mass of the new disc is R from the center of the bigger disc. the value of is a. 1/3 b. 1/2 c. 1/6 d. 1/4 59. 57 Problem Which of the following parameters dose not characterize the thermodynamic state of matter? a. Temperature b. Pressure c. Work d. Volume 60. 58 Problem A charged oil drop is suspended in uniform field m of 3 x104 V/m so that it neither falls nor rises .the charge on the on the drop will be (take the mass of the charge = 9.9x10 15 kg and g =10m/s 2) a. 3.3 x 10-18 C b. 3. 2 x 10-18 C c. 1.6 x 10-18 C d. 4. 8 x 10-18 C 61. 59 Problem For a cubic crystal structure which one of the following relations indicating the cell characteristic is correct ? a. a b c and and 900 b. a b c and 900 c. a b c and 900 d. a b c and 900 62. 60 Problem A common emitter amplifier has a voltage gain of 50, an input impedance of 100 and an output impedance of 200 . The power gain of the amplifier is a. 500 b. 1000 c. 1250 d. 100 63. 61 Problem The phase difference between the instantaneous velocity and acceleration of a particle executing simple harmonic motion is a. 0.5 b. c. 0.707 d. zero 64. 62 Problem A vertical spring with force constant k is fixed on a table. A ball of mass m at height h a above the free upper end of the spring falls vertically on the spring so that the spring is compressed by a distance d. the net work done in the process is a. mg(h + d) + 1/2kd2 b. mg(h + d) 1/2kd2 c. mg (h - d) 1/2kd2 d. mg (h - d) + 1/2kd2 65. 63 Problem Dimensions of resistance in an electrical circuit in terms of dimension of mass M, of length L , of time and of current I would be a. [ML2T-3I-1] b. [ML2T-2] c. [ML2T-1I-1] d. [ML2T-3I-2] 66. 64 Problem A particle moving along x- axis has acceleration f, at time t, given by f = f0 , the particle at t = 0 has zero velocity ,in instant when f = 0 .the particle s velocity (vx) is a. f0T b. f0T2 c. f0T2 d. f0T 67. 65 Problem An alpha nucleus of energy 1/2mv2 bombards a heavy nuclear target of charge Ze. then the distance of closed approach form the alpha nucleus will be proportional to a. v2 b. 1/m c. 1/v4 d. 1/Ze 68. 66 Problem The work of 146 kJ is performed in order to compress one kilo mole of gas adiabatically and in this process the temperature of the gas increases by 70 C. the gas is (R=8.3J mol-1k-1) a. diatomic b. tritomic c. Amixture of monoatomic and diatomic d. Monoatomic 69. 67 Problem If gE and gM are the accelerations due to gravity on the surface of earth and the moon in the earth and the moon respectively and if millikans oil drop electronic charge on themoon experiment could be performed on the ratio to be electronic charge on the earth a. 1 b. ZerogE c.gMgM d.gE 70. 68 Problem Diwali rocket is ejecting 50 g of gases/s at a velocity of 400 m/s. The accelerating force on the rocket will be a. 22 dyne b. 20 N c. 20 dyne d. 100 N 71. 69 Problem A frame made of metallic wire enclosing a surface area A is covered with a soap film. If the area of the frame of metallic wire is reduced by 50%, the energy of the soap film will be changed by a. 100% b. 75% c. 50% d. 25% 72. 70 Problem Mercury boils at 3670C. However, mercury thermometers are made such that they can measure temperature upto 5000C. This is done by a. Maintaining vacuum above mercury column in the stem of thethermometer b. Filling nitrogen gas at high pressure above the mercury column c. Filling oxygen gas at high pressure above the mercury column d. Filling nitrogen gas at low pressure above the mercury column 73. 71 Problem In a laboratory four convex lenses L1, L2, L3 and L4 of focal lengths 2, 4, 6 and 8 cm, respectively are available. Two of these lenses form a telescope of length 10 cm and magnifying power 4. The objective and eye lenses are respectively a. L2, L3 b. L1, L4 c. L1, L2 d. L4, L1 74. 72 Problem A symmetric double convex lens is cut in two equal parts by a plane perpendicular to the principal axis. If the power of the original lens is 4D, the power of a cut lens will be a. 2D b. 3D c. 4D d. 5D 75. 73 Problem Two non-ideal batteries are connected in parallel. Consider the following statements. (i) the equivalent emf is smaller than either of the two emfs. (ii) The equivalent internal resistance is smaller than either of the two internal resistances. a. Both (i) and (ii) are correct b. (i) is correct but (ii) is wrong c. (ii) is correct but (i) is wrong d. Both (i) and (ii) are wrong 76. 74 Problem For a metallic wire, the ratio V/i (V = applied potential difference and I = current flowing) is a. Independent of temperature b. Increases as the temperature rises c. Deceases as the temperature rises d. Increases or decreases as temperature rises depending upon the metal 77. 75 Problem The potential energy of a molecule on the surface of a liquid compared to one inside the liquid is a. Zero b. Lesser c. Equal d. Greater 78. FOR SOLUTIONS VISIT WWW.VASISTA.NET