CET PHYSICS 2011 VERSION CODE: A 4

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1 dislacement CET PHYSICS 0 VERSION CODE: 4. If C be the caacitance and V be the electric otential, then the dimensional formula of CV is ) M L T ) M 0 L T 0 ) M L T 4) M L T 0 CV Energy The dimentional formula is ML T -. The dislacement-time grahs of two moving articles make angles of 0 o and 45 o with the X-axis. The ratio of their velocities is. ) : ) : ) : 4) : O 45 o 0 o time ns: () Sloe of dislacement time grah is velocity v v Tan Tan Tan0 Tan :. lock of mass kg is laced over block of mass 8 kg. The combination is laced over a rough horizontal surface. Coefficient of friction between and the floor is 0.5. Coefficient of friction between and is 0.4. horizontal force of 0 N is alied on block. The force of friction between and is. ns: () ) zero ) 50 N ) 40 N 4) 00 N Net frictional force between block and surface is F (R) 0.5 x 0 x 0 50 N lied force is 0N and it is less than 50 N System is at rest and No friction between and kg 8 kg 0 N 4. The height y and the distance x along the horizontal lane of a rojectile on a certain lanet (with no surrounding atmoshere) are given by y 8t 5t metre and x 6t metre, where t is in seconds. The velocity with which the rojectile is rojected is ) 4 ms ) 0 ms ) 8 ms 4) 6 ms

2 ns: () x (u cos ) t 6 u cos t x 6 y (u sin )t gt y 8t 5t u sin 8 u 0 m/s 5. body of mass 5 kg is thrown vertically u with a kinetic energy of 490 J. The height at which the kinetic energy of the body becomes half of the original value is.. ).5 m ) 0 m ).5 m 4) 5 m ccording to law of conservation of energy mu mv + mgh x 9.8 x h 45 h 5m solid shere of mass m rolls down an inclined lane without sliing, starting from rest at the to of an inclined lane. The linear seed of the shere at the bottom of the inclined lane is v. The kinetic energy of the shere at the bottom is 7 ) mv 0 ) 5 mv ) 5 mv 4) mv ns: () Total KE at bottom: mv K mv R 7 mv Two satellites of mass m and 9 m are orbiting a lanet in orbits of radius R. Their eriods of revolution will be in the ratio of.. ns: () ) : ) : ) : 4) 9: Time eriod is indeendent of mass 8. The following four wires of length L and radius r are made of the same material. Which of these will have the largest extension, when the same tension is alied? ) L 400 cm, r 0.8 mm ) L 00 cm, r 0.6 mm ) L 00 cm, r 0.4 mm 4) L 00 cm, r 0. mm y F x e

3 e r () e 0 () e () e 8 (4) e The resultant of two forces acting at an angle of 0 o is 0 kg wt and is erendicular to one of the forces. That force is.. ) ns: () 0 kg wt ) 0 kg wt ) 0 kg wt 4) 0 kg wt Tan 0 x 0 x x 0 F 0 0 F 0 0. Eight equal dros of water are falling through air with a steady velocity of 0 cm s. If the dros combine to form a single dro big in size, then the terminal velocity of this big dro is. ) 80 cm s - ) 0 cm s - ) 0 cm s - 4) 40 cm s - V r 0 r / v 8 r 4 F v v r r v 40 cm/s. Two caillary tubes of different diameters are died in water. The rise of water is ) indeendent of the diameter of the tube ) greater in the tube of smaller diameter ) greater in the tube of larger diameter 4) the same in both tubes ns: () h r greater for the tube of smaller diameter

4 . erfect gas at 7 o C is heated at constant ressure so as to double its volume. The increase in temerature of the gas will be. ns: () ) 00 o C ) 54 o C ) 7 o C 4) 600 o C V T V T T 600 K 7 0 C 00 T t C. Three identical rods, and C are laced end to end. temerature difference is maintained between the free ends of and C. The thermal conductivity of is THRICE that of C and HLF of that of. The effective thermal conductivity of the system will be.. (K is the thermal conductivity of rod ). ns : (4) ) K ) K ) K 4) K C K K / K K C K C K /6 K C K K C K 9 K S K K K S K K K K 6 4. The quantities of heat required to raise the temeratures of two coer sheres of radii r and r (r.5 r ) through K are in the ratio of.. ) ) Heat required is roortional to square of radius ) ) 8 Q Q r r

5 5. Which one of the following is v m T grah for erfectly black body? V m is the frequency of radiation with maximum intensity. T is the absolute temerature. ) D ) C ) 4) ns : () Intensity is directly roortional to energy. vm (Hz) C D T (K) 6. article executing a simle harmonic motion has a eriod of 6 sec. The time taken by the article to move from the mean osition to half the amlitude, starting from the mean osition is ns : () ) 4 sec ) 4 sec ) sec 4) sec y sin t T sin t T π t T 6 π t /6 T 7. The equation of a wave is given by y 0 sin t. If the dislacement is 5 cm at 45 t 0, then the total hase at t 7.5 sec. is ) ) 6 ) 4) ns : () π y 0 sin t α 45 If t 0, y 5 cm 5 0(sin ) sin 6 If t 7.5 s Then total hase 5 x

6 8. Two tuning forks, and, roduce notes of frequencies 58 Hz and 6 Hz. n unknown note sounded with roduces certain beats. When the same note is sounded with, the beat frequency gets doubled. The unknown frequency is ns: () ) 56 Hz ) 54 Hz ) 00 Hz 4) 50 Hz 58 Hz 6 Hz Let is the frequency of unknown tuning fork. It roduces x beats with 58 and x with 6 6 (58 x) x x x x 4 54 Hz 9. wire under tension vibrates with a fundamental frequency of 600 Hz. If the length of the wire is doubled, the radius is halved and the wire is made to vibrate under one-ninth the tension. Then the fundamental frequency will become ) 400 Hz ) 600 Hz ) 00 Hz 4) 00 Hz f r T f f r x r T T 600 x f T T / 9 f 00 Hz 0. Faintest stars are called ) dwarfs ) sixth magnitude stars ) second magnitude stars 4) zero magnitude stars ns: (). Wavelength of given light waves in air and in a medium are and resectively. The critical angle is ns: () ) Sin η η sinc sinc C sin (/) ) Sin ) Tan 4) Tan 6

7 . The time required for the light to ass through a glass slab (refractive index.5) of thickness 4 mm is. (c x 0 8 ms, seed of light in free sace). ) x 0 5 sec ) x 0 + sec ) x 0 sec 4) 0 sec n n g a c a c g t dis tance seed x 0 cg c g x x 0 8 x 0 x 0 - s. rism having refractive index.44 and refracting angle 0 0 has one of the refracting surfaces silvered. beam of light incident on the other refracting surface will retrace its ath, if the angle of incidence is.. ns: () ) 45 0 ) 60 0 ) 0 0 4) 0 0 r 0 ( No refraction is there at second surface) r 0 o n sini sinr sini o sin0 x sin i i 45 o 4. lanoconvex lens has a maximum thickness of 6 cm. When laced on a horizontal table with the curved surface in contact with the table surface, the aarent deth of the bottommost oint of the lens is found to be 4 cm. If the lens is inverted such that the lane face of the lens is in contact with the surface of the table, the aarent deth of the center of the lane face is found to be 7 cm. The radius of curvature of the lens is.. 4 ns: () ) 4 cm ) 8 cm ) 75 cm 4) 68 cm n real deth aarentdeth n n + ~ n u v R.5 6 n R R 4 cm 4 6 7

8 5. Two thin lenses have a combined ower of +9 D. When they are searated by a distance of 7 0 cm, their equivalent ower becomes + D. Their individual owers (in dioters) are 5 ns: ().. ) 4, 5 ), 6 ), 7 4), 8 P + P 9 P P + P dp P x P P 5 00 The above equation is correct for P, P 6 6. Wavefront is the locus of all oints, where the articles of the medium vibrate wit the same. ) eriod ) frequency ) amlitude 4) hase Over the wave front all the oints are in same. 7. Two monochromatic light waves of amlitudes and interfering at a oint have a hase difference of The intensity at the oint will be roortional to.. ns: () ) 9 ) 7 ) 4) 5 cos I x x x 9 8. Consider the following statements in case of Young s double slit exeriment. a) slit S is necessary if we use an ordinary extended source of light. b) slit S is not needed if we use an ordinary but well collimated beam of light. c) slit S is not needed if we use a satially coherent source of light. Which of the above statements are correct? ) (a) and c) ) (b) and c) ) (a) and (b) 4) (a), (b) and (c) ns: () 9. arallel beam of light of wavelength gets diffracted by a single slit of width 0. mm. The angular osition of the first minima of diffracted light is. ) 6 x 0 rad ).8 x 0 rad ) x 0 rad 4) x 0 rad dsin n 0. x 0 - x 6000 x 0-0 x 0 - rad 8

9 0. The critical angle of a certain medium is Sin. The olarizing angle of the medium is 5.. ) Tan 4 tan i sinc ) Tan 4 ) Tan 5 4) Sin 4 5 cot i sin tan i 5 sin 5 i tan 5. Two identical charged sheres of material density, susended from the same oint by inextensible strings of equal length make an angle between the strings. When susended in a liquid of density the angle remains the same. The dielectric constant K of the liquid is.. ) r F F a m ) mg ρv ρ (m m )g (ρ σ)v ρ σ l ) 4). The electric field at a oint due to an electric diole, on an axis inclined at an angle (< 90 0 ) to the diole axis, is erendicular to the diole axis, if the angle is. ns: () ) Tan + 90 o tan tan tan tan (90 - ) tan tan ( ) ) Tan ) Tan ) 4) Tan () E 9

10 . In the circuit shown, the currents i and i are ) i, i ) i, i ) i 0.5, i.5 4) i.5, i 0.5 R I x 4 4 E R r I + I I R I 0.5, I.5 i i 4 V, 4. In the given network, the value of C, so that an equivalent caacitance between and is F, is ) 6 F C F ) 48 F 6 F 4 F ) F 5 F F 4) F 5 ns: () 6 C 5 C 48 F 6 C 5 C 6/5 F F 8 F 5. conductor wire having 0 9 free electrons/m carries a current of 0. If the cross-section of the wire is mm, then the drift velocity of electrons will be.. ) 6.5 x 0 ms ).5 x 0 5 ms ).5 x 0 ms 4).5 x 0 4 ms I v d ne 0.5 x 0 - ms - X0 x.6 x resistor has a colour code of green, blue, brown and silver. What is its resistance? ) % ) 560 5% ) 560 0% 4) 56 5% R 56 x 0 0% 560 0% 0

11 7. The voltage V and current I grahs for a conductor at two different temeratures T and T are shown in the figure. The relation between T and T is ) T T ) T T ) T < T V T T 4) T > T Sloe of V I grah Resistance Resistance temerature R > R T > T O I 8. Consider the following statements regarding the network shown in the figure. ns: () a) The equivalent resistance of the network between oints and is indeendent of value of G. b) The equivalent resistance of the network between oints and is 4 R. c) The current through G is zero. Which of the above statements is/are TRUE? ) (a), (b) and ( c) ) (b) and (c) ) (b) alone 4) (a) alone (P Q)(R G) 4 R eff R (P Q R G) 9. The torque required to hold a small circular coil of 0 turns, area mm and carrying a current of is the middle of a long solenoid of 0 44 turns/m carrying a current of.5, with its axis erendicular to the axis of the solenoid is. ).5 x 0 +8 N-m ).5 x 0 +6 N-m ).5 x 0-8 N-m 4).5 x 0-6 N-m c M (n I ) ( 0 n I ) XIS x x0 4 x x0 x0 x.5.5 x 0 8 Nm 44 7 R R E COIL G R R SOLENOID

12 40. article of charge e and mass m moves with a velocity in a magnetic filed alied erendicular to the motion of the article. The radius r of its ath in the field is. ) em mv mv r q e e ) m ) e m m 4) e 4. neutron, a roton, an electron and an - article enter a region of uniform magnetic field with the same velocities. The magnetic field is erendicular and directed into the lane of the aer. The tracks of the articles are labelled in the figure. The electron follows the track ) D ) C ) 4) ns: () mv r q r is least when m q m q is least is least for electron. i.e. ath is D C D 4. The deflection in a moving coil galvanometer is reduced to half when it is shunted with a 40 coil. The resistance of the galvanometer is ) 5 ) 0 ) 40 4) 80 I I g I S G S 40 G 40 G current of factor is roduces a deflection of 60 o in a tangent galvanometer. The reduction ) ) ) 4)

13 K I tan tan In an.c. circuit, V and I are given by V 50 Sin (50t) volt and I 50 Sin 50 t amere. The ower dissiated in the circuit is ns: () ) zero ) 565 W ) 50 W 4) 06 W P V0 I 0 cos 0.5 x 50 x 50 x cos w In the L-C-R circuit shown, the imedance is ns: () ) 500 ) 00 ) 00 4) 00 X L fl X C fc 50 x x L H C R 0 F 00 ~ 50 V, Hz Z R (X X ) ( 00) (400) 500 C L 46. The energy stored in an inductor of self inductance L henry carrying a current of I amere is ) L I ) LI ) LI 4) L I u LI 47. transformer works on the rincile of ) magnetic effect of the electrical current ) mutual induction ) electrical inertia 4) self induction ns: () Mutual induction

14 48. Flash sectrum confirms a/an ) magnetic storm ) earthquake ) lunar eclise 4) total solar eclise Total solar eclise 49. The hotoelectric threshold wavelength for silver is 0. The energy of the electron ejected from the surface of silver by an incident wavelength ( < 0 ) will be 0 ) hc h ) 0 c 0 ) 0 hc 0 4) hc( 0 - ) ns: () E W + K.E K.E. E W hc - hc o hc o o hc o 50. Rutherford s atomic model could account for ) concet of stationary orbits ) the ositively charged central core of an atom ) origin of sectra 4) stability of atoms ns: () The ositively charged central core of an atom 5. When an electron jums from the orbit n to n 4, then wavelength of the radiations absorbed will be (R is Rydberg s constant). R ) 6 R n n n, n 4 5 R ) 6 4 R R R R 6 ) 6 5 R 4) 6 R 4

15 5. The thermonuclear reaction of hydrogen inside the stars is taking lace by a cycle of oerations. The articular element which acts as catalyst is ns: () ) carbon ) helium ) oxygen 4) nitrogen In carbon cycle carbon is a reactant as well as end roduct 5. The ratio of minimum wavelength of Lyman and almer series will be ) 0 ) 5 ) 0.5 4).5 n Lymann almer The fraction of the initial number of radioactive nuclei which remain undecayed after half of a half-life of the radioactive samle is ) ) ) ns: () N0 N0 N0 N n / 4) curie reresents ) disintegration er second ) 0 6 disintegrations er second ).7 x 0 0 disintegrations er second 4).7 x 0 7 disintegrations er second ci.7 x 0 0 dis / sec 56. n n--n transistor can be considered to be equivalent to two diodes, connected. Which of the following figures is the CORRECT ONE? ) ) C E ) C 4) E E n n C E E C C 5

16 57. In the case of forward biasing of a -n junction diode, which one of the following figures correctly deicts the direction of conventional current (indicated by an arrow mark)? ) ) n - + ) 4) - + n - + n - + n ns: () In region direction of conventional current is same as flow of holes In n region direction of conventional current is oosite to direction of flow e - s. 58. n electron of mass m e and a roton of mass m are moving with the same seed. The ratio of their de-roglie s wavelength e / is ) 98 ) 86 ) 86 4) e h m v h m v e h mv m m 7.67 x 0 m e 9. x x OR e m m e mass of roton is near 840 times of electron. 59. The outut of given logic circuit is ) + + C ) ) ( + ). ( + C) ). (. C) 4).( + C) C Y ns: () ) OR + ND ( + ). ( + C) Y C OR + C 6

17 60. If the scattering intensity of a liquid is 8 units at a wavelength of 500 nm, then the scattering intensity at a wavelength of 400 nm will be aroximately ns: () ) 4 units ) 0 units ) 6 units 4) units I 4 I I 4 I I I I (.5) 8 x

PHYSICS. [Time 3 hours] [Maximum Marks: 720]

PHYSICS. [Time 3 hours] [Maximum Marks: 720] CBSE MAINS-07 PHYSICS [Time 3 hours] [Maximum Marks: 70] General Instructions:. The Answer Sheet is inside this Test Booklet. When you are directed to open the Test Booklet, take out the Answer Sheet and