TEST BOOKLET

DO NOT OPEN TIllS TEST BOOKLET UNTIL YOU ARE ASKED TO DO SO
Test Booklet Series B BAC-50 PHYSICS Serial No. 914182
Time AUowed 2 Hours Maximum Marks: 300

INSTRUCfIONSTO CANDIDATE
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IDO NOT OPEN THIS BOOKLET UNTIL YOU ARE ASKED TO DO SO I

1. The coefficient of finesse of Fabrey-Perot interferometer depends on

the amplitude of incident wave


the phase difference between two successive waves emanating from the same plate


the film thickness


the reflectivity of plates


2. An unpolarized plane wave on a calcite crystal splits up into the 0-and e-waves. Following statements are given about these waves.
.... ....
A. D.K 0 for both 0-and e-waves
.... ....

B. For the e-wave, D lies in the plane containing K and optic axis of the crystal
C. The ray velocity surfaces corresponding to ordinary ray are ellipsoid of revolution The correct option is

A only AandB


AandC A,BandC


3. Which of the following phenomenon is mainly responsible for the red colour of the rising Sun and blue colour of the Sky

Raman scattering Rayleigh scattering


Mie scattering Compton scattering


4. In which process, the energy delivered by the atomic or molecular system has same field distribution and frequency as the inducing radiation?

Spontaneous emission


Stimulated emission


Stimulated absorption


Both spontaneous and stimulated emissions


S. An atomic line of wavelength 6000 Ahas a coherent length of 36 cm. The line-width of the line is

0.01 A 0.1 A


1.0 A 10.0 A


Serles-B 2 BAC-SO
6. The lateral coherence length of an extended incoherent source of wavelength A subtending an angle eat the point of observation is
A
Ae e
2
e A
e
A
7. The diffraction pattern due to double slit having slit-width and the separation between the slits changes to

that due to a single slit pattern of width if tends to zero.


fringes obtained in the Young's interference experiment if tends to zero.


the single slit pattern if tends to zero.


the spot of light if tends to zero.


8. The missing orders of a double slit Fraunhofer diffraction pattern for slits of width each separated by are




12, 18


9. To resolve the D1 and D2 lines of sodium in the! second order, the total number of lines in the plane diffraction grating must be at least

200 300


SOO lOOO


10. The radii of a zone-plate are given by the expression 0.02;[n em. For the
n
monochromatic light of wavelength 4000 the most intense focal point will be at a distance

10em 20em


100 em 200 em


11. If a linearly polarized beam of light is incident on a half-wave plate making an angle of 45° with the optic axis, the

beam gets converted to a circularly polarized wave


beam gets converted to an elliptically polarized wave


plane of polarization gets rotated by 90°


plane of polarization gets rotated by 1800


BAC-SO 3 Serles·B
12. Which of the following is/are dichroic material?

Tourmaline


Polyvinyl alcohol film All of the above


13. The temperature of the liquid hydrogen is 20 K. The equivalent temperature on the of scale is

-253 -423


-432 none of these


14. A 70 L petrol tank made of steel is filled to the top with petrol at 20°C. If the temperature of the tank rises to 40 the quantity of petrol that will overflow from the tank is (given: coefficient of volume expansion of petrol 950 x 10-6 (cotl)

1.0 L 1.1 L


1.3 L 1.4 L


15. For a given quantity of gas, the corresponding statements of proportionaity for the Boyle's law, Charles's law and Gay-Lussac's law respectively, are

PIX V IX V IX lIP V IX V IX lIP, P IX T


V IX lIP, V IX P IX T None of these


16. An automobile tire is filled to a gauge pressure of 200 kPa at 10°C. After driving 100 km, the temperature within the tire rises to 40°C. Assuming the atmospheric pressure 101 kPa, the pressure within the tire now is

333 kPa 301 kPa


200 kPa 232 kPa


17. The ideal gas law is an accurate description of the behaviour of a real gas at

all pressures and temperatures


all pressure and at temperatures very near to the liquefaction point of the gas


all temperatures and at pressure below 1 atm


temperatures far from the liquefaction point of the gas and when pressure is not too high


Series-B 4 BAC-50
18. A refrigerator converts 1.5 kg of water at 20°C to ice at the amount of energy removed by the refrigerator is (given: specific heat of water =4180 Co, specific heat of ice 2100 Co, latent heat of fusion of water 3.33 x 105

660 kJ 560 kJ


460 kJ none of these


19. A clock having a pendulum made of brass, is adjusted to have a period of I s exactly at 20°C. The clock is then operated at 30 °C for I week. The clock will be in error [given: coefficient of linear expansion for brass 19.3 x (COtll,

60 s slower 60 s faster


20 s slower 20 s faster


20. The heat needed to raise 1 kg of water by I Co, from 14.5 °C to 15.5 °C is called

Joule Calorie


caloire kJoule


21. The specific heat of iron .is 450 Jl1<g . Co. The heat required to raise the temperature of an empty 20 kg vat made of iron is

7.3x103J 7.2x1()4J


7.2 X 105 J 7.3 x 106 J


22. The thennal conductivity of a window glass is 0.84 J/s·m·Co. The rate of heat flow through this glass window of area 2 m x 1.5 m and thickness 3.2 mm with inner temperature =15°C and outer temperature =14 is

680 kcallh 790 J/s


0.19 kcalls All of these


23. The process of transfer of heat by the mass movement of molecules from one place to another is termed as

conduction convection


rarnation reduction


24. A 6 g bullet melts at 300 °C. It has a specific heat capacity of 0.20 cal/g'Co and heat of fusion of 0.15 callg. The amount of heat needed to melt the bullet if it is originally at 0 is

360 calorie 1504.8 J


376.2 calorie 450 calorie HAC-SO 5 Series-B


25. A partially inflated balloon containing 500 m3 of helium gas at 27°C and at 1 atm pressure rises to an altitude of 18000 ft, where the pressure is 0.5 atm and the temperature is _3°C. The volume ofthis balloon is now

900 m3 700 m3


600 m3 none of these


26. A process in which no heat transfer takes place into or out of the system and is meaningful in both quasistatic and more violent processes is termed as

isothermal process isobaric process


adiabatic process none of these processes


27. The second law of thermodynamics can be stated as

heat flows naturally from a hot object to a cold object, heat will not flow spontaneously from a cold object to a hot object.


there can be 110 100 percent efficient heat engine -that is, one that can change a given amount of heat completely into work.


natural process tend to move toward a state of greater disorder or greater entropy.


all the above mentioned statements.


28. The most probable state of air molecules in a close room will follow

non-linear distribution Maxwellian distribution


Gaussian distribution None ofthese


29. An ideal Carnot engine takes heat from a source at 317°C, does some external work and delivers the remaining energy to a heat sink at 117 0C. If 500 kcal of heat is taken from the source, then the amount of work done is

831 kcal 160 kcal


331 kcal 169 kcal


30. Assuming the heat of vaporization of water to be 540 kcal/kg, the change in the entropy of
2.00 kg of HzO molecules when transformed at a constant pressure of 1 atm from water at
100°C to steam at the same temperature is

12.12 kJ/K 13.12 kJ/K


14.12 kJ/K 15.12 kJlK


31. The value of Stefen-Boltzman constant is 5.67 x 1<r8 W/m2K4. A spherical blackbody of 5 cm radius is maintained at a tempeature of 327°C. The power radiated is

231 W 331 W


431W none of these


Series-B 6 BAC-50
32. A steam engine operates between 500°C and 270 °C. The carnot efficiency of this engine is

70% 46%


30% 54%


33. Crystal lattices act as diffraction gratings to X-rays as X-rays

are highly penetrating


are highly energetic


are highly coherent


possess matching wavelengths to lattice constants


34. X-ray diffractions occur only in

single crystalline solids


polycrystalline solids


both in single crystalline and polycrystalline solids


amorphous solids.


35. The Miller indices of a set of lattice planes in a cubic crystal of lattice constant a are The separation. between these lattice planes is
a
d=a

..J2
a
..j3 d="2
36. The separation between successive planes in a set of parallel lattice planes is

directly proportional to the values of their Miller indices.


inversely proportional to the values of their Miller indices.


is not related to their Miller indices.


none of these above.


37. Which of the following equations generate a general three dimensional lattice (The symbols· used have their usual significance)

T=r'±nx
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38. A f.c.c. unit cell can be converted to a b.c.c. unit cell if

the direct lattice unit cell is represented in the recil'rocallattice


mirror inversion is given to the direct lattice unit cell


the direct lattice unit cell is given a rotation through a 4-fold axis of symmetry


none of these are correct


39. If a semiconducting material is cooled to 0 its conductivity will be

infinite zero


like that of an ordinary metal negative


40. The electrical conductivity of an intrinsic semiconductor increases exponentially with temperature

this is due to increase of carrier densities with temperature exponentially


this is due to exponential increase of mobility of the carriers with temperature


this is due to breaking of the bondings due to temperature increase


this is due to ionization of inner electronic shells at higher temperatures


41. Assertion The nature of temperature dependence of electrical conductivity in intrinsic and extrinsic semiconductors is of the same type.
Reason This is due to the reason that the nature of temperature excitation of carriers in intrinsic and extrinsic semiconductors is the same.

is true and is the correct reason for it.


is true but is false.


is false but is true.


Both and are false.


42. Assertion For full wave rectification a four diodes bridge circuit is preferred compared to a two diodes circuit.
Reason This is for the reason that the peak inverting voltage needed in the four diodes bridge can be only half that of two diodes circuit.
is correct and is the true explanation.
is correct but is false.
is false but is correct.
Both and are false.

Serles·B 8 BAC-SO
43. Assertion A p-n junction diode is fabricated by joining p and n blocks under pressure. Reason In this way a proper junction layer is realised.

Both and are false.


is true but is false.


is false but is true.


is true and is the correct explanation of it.


44. Assertion In a p-n junction diode the built-in contact potential gradient is determined by the difference of the Fermi levels on the p and n sides at the instant of formation of the contact.
Reason This is due to the reason that transfer of carriers across the junction ceases when the Fermi levels on both sides of the junction coincide.

is true and is the correct explanation for it.


is true but is false.


is false but is true.


Both and are false.


45. Assertion A zener diode is used as a voltage stabilizer.
Reason This is for the reason that at the zener voltage, the voltage remains unchanged.

is true and is the correct reason for it.


is true but is false.


is false but is true.


Both and are false.


46. Assertion In a zener diode zener action is due to generation of large number density of charge carriers as a result of ionization of inner electronic shells of atoms.
Reason This is because the high applied bias voltage causes ionization of core electronic shells of atoms.

is true but is false.


is true and is the correct cause of it.


is false but is true.
Both and are false.
BAC-SO 9 Series-B

47. Assertion In a transistor the base region is made comparatively thinner than the
emitter and collector regions. Reason This is to make the transit times of the charge carriers low in the base.

is true and is the correct explanation of it.


is true but is false.


is false but is true.


Both and are false.


48. In a common emitter transistor configuration

the output voltage is in phase with the input voltage.


the output and input voltages differ by 1800 in phase.


the output is 90° out of phase with the input.


the output is 45° out of phase with the input.


49. Assertion In a transistor amplifier the output impedance is made high. Reason This is to achieve high voltage amplification.

is true and is the correct explanation of it.


is true but is false.


is false but is true.


Both and are false.


50. Answer, the work function of metals is related to which component of a vacuum diode.

plate current


cathode -anode separation


cathode to anode potential difference


emission of carriers (electrons) from the filament


51. Answer, which are the Universal gates that can perform all the logic functions.

NAND and NOR NAND and OR


OR and NOR None of these combinations


52. Assertion Digital computers are better than analogue computers. Reason Due to their high speed of functioning and accuracy of the work.
is true and is the correct cause of it.
is true but is false.
is false but is true.
Both and are false.
Series·H 10 HAC·SO

53. According to Gauss law, the number of electric field lines crossing the closed surface is

Numerically equal to the enclosed charge.


Equal to the enclosed positive charge.
. Equal to the electric field inside the surface.



Equal to the charge density on the surface.


54. The potential due to a point charge x coulomb at a point which is at a distance of 30 cm from it is
900 V -900 V
-3000 V 300 V
55.· The work done by carrying a charge of 5 from a point A to B is 8 mJ. The difference of potential between A and B is

160 V 16 V


1.6 kV 16 kV


56. A parallel plate capacitor is formed of two plates of area separated by a distance with air between them. The capacitance will be

EoAd EoNd


Eod/A EiAd


57. Four capacitors are connected as shown in figure below, then the equivalent capacitance between point P and Q is
p llll' Q


tlll'

4llF 'hllF


*llF 4/3llF


58. The electric dipole moment per unit volume of the dielectric is called

Polarization of dielectric


Electric displacement of vector


Dipole density


None of the above


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59. The charge on an isolated conductor always lies

Within the conductor. at the centre of the conductor.


on the surface of the conductor. just outside the surface.


60. Two capacitors of 1 IlF capacitance each are connected in parallel and are then charged by 200 V d.c. The total energy in joules is

0.01 0.02


0.04 0.06


61. Which of the following is not affected by the internal resistance?

terminal potential difference


emf of the source


current delivered to external circuit


power output


62. The poynting vector gives the direction of

Electric field Magnetic field


Power flow None of these


63. Two circular coils have radii in the ratio 1:2 with the same number of terms. The ratio of magnetic field produced at the centre of the coils when connected in series is
W 00
2

64. In a synchrotron the magnetic field must change to compensate the

heating of coils.


loss of energy due to air resistance.


increase in the radius of circular path.


None of these


65. Ferromagnetic substances have

high permeability and low susceptibility.


low permeability and high susceptibility.


both permeability and susceptibility are low.


both permeability and susceptibility are high.


Series-B 12 BAC-SO
66. The emf produced in a wire by its motion across a magnetic field does not depend on the

length of the wire composition of the wire


diameter of the wire orientation of the wire


67. The varying magnetic' field through conductor produces electromotive force. This is in accordance with

Faraday's law Lenz law


Laplace law Ampere's law


68. The frequency for which a 5.0 Iil' capacitor has a reactance of 1000 12 is given by

looO/n cycles/sec looht cycles/sec


200 cycles/sec 5000 cycles/sec


69. In a parallel LCR circuit, at resonance,

current is maximum voltage is maximum


impedance is minimum impedance is zero


70. A capacitor of 0.5 Iil' is discharged through a resistance of 10 M12. The time taken for half of the charge on capacitor to leak is

1.6 sec 3.2 sec


4.8 sec 6.0 sec


71. In a purely inductive circuit, the current

lags behind emf by 900 leads the emf by 900


is in phase with emf may lead or lag the emf


72. A spherical capacitor consists of two concentric spherical shells of radii and with b>a. Its capacitance is

4n 4n Eoab


4n 4n


73. According to Bohr's principle, the relation between the principal quantum number and radius of the orbit, is

roc lin roc n


roc n2 roc lIn2


HAC·SO 13 Series·B
74. Neglecting variation of mass with velocity, the de Broglie wavelength associated with an electron moving with kinetic energy E is proportional to

EII2 E-1I2


E B-2


75. The uncertainty relation cannot hold for the following pairs

Position and linear momentum


Energy and time


Angular momentum and angle


,Linear momentum and angle


76. The ionization potential of hydrogen atom is 13.6 eV. The energy required to remove an electron from the orbit of hydrogen is

1.51 eV 3.4 eV


6.8 eV 13.6eV


77. The wavefunction of a bound particle is A cos2x for -rrJ2 x rrJ2. The value of A is

112 (3/81t)112


(l/21t)112 (3121t)1I2


78. 9OTh232, an isotope of Thorium decays in ten stages emitting six <X-particles and four fl­particles in all. The end product of the entire decay process is
82Pb209



83Br209


79. After two hours,· (1I16)th of initial amount of a certain radioactive isotope remains undecayed. The half life of the isotope is about
15 min 30 min
45 min 7.5 min Serles-B 14 BAC·50
80. Energy levels Band C of a certain atom correspond to increasing values of energy i.e.,
EA< En Ec-If and A3 are wavelengths of radiation corresponding to the transitions C to B to Aand C A respectively, which one of the following relations is correct?
A3 1..( 1..2 Al
22 2

1..3 =1..1 +1..2 1..3 A]A2 (AI A2)
81. The work functions for metals Band C are respectively 1.9 eV, 2.5 eV and 5.6 eV. According to Einstein's theory for photoelectric effect, the metal/metals which will emit photo-electrons for a radiation of wavelength 4100 A is/are [given Planck's constant h 6.6 X 10-34 J.sec; 1 eV 1.6 x 1O-19J]

None A only


A and B only all the three metals


82. The spin angular momentum of an electron (in terms of the Planck's constant is

always the same h/4n


always the same h/2n


integral multiples of h/2n


V2)(hl2n) where N ....


83. The ground state wavefunction of a particle trapped in a one-dimensional box of width L is =(2IL)112 sin (nxIL). The expectation value of the coordinate of the particle, x is

0 U2


U4 L


84. Electrons with energy of 1.0 eV are incident on a potential barrier 5.0 eV high and 0.5 nm wide nm 10-9 m). The transmission probability T is of the order of [given mass of electron -9.1 x 10-31 kg, b 1.054 X 10-34 J.sec, 1 eV 1.6 x 10-19
10-10
10-14 10-2
elt
85. An eigen function of the operator d2/<J.x2 is The corresponding eigen value is
1 2
8 BAC·SO 15 Series-B
86. X-rays of wavelength 10.0 pm pm 10-12 lire scattered from a larget al an angle of
45°. If the electron Compton wavelength Ac =2.426 pm, then the smallest wavelength of the scattered X-rays is

10.7 pm 20.0pm


9.71 pm 10.0 pm


87. The distance between adjacent atomic planes in a calcite (CaC03) crystal is 0.30 pm. The smallest angle of Bragg's scattering for 0.03 nm X-rays is

1.2° 1.9°


2.1° 2.9°


88. The spin, charge and baryon number of the quark are respectively

1/3 1/3


1/3 1/3


89. In the reaction IW IH3 2He4 onl, if the binding energies of IW, IH3 and 2He4 are respectively band c (in then the energy (in MeV) released in this reaction is







90. The uncertainty product <iK Llp for the nth eigen state of a one-dimensional harmonic oscillator is

n 112)





91. The hydrogen atom is in d-state. For this state, the .value of the magnetic quantum number m is
2,1,0

92. The wavefunction of a particle is given by c exp (-x2ex2 where c and ex are constants. The probability of finding the particle in the region 0 x oc is

1 1/3


1/2 1/4


Series-B 16 BAC-50
93. The aim of Michelson Morley experiment was to

measure velocity of light
measure refractive index of glass



prove that special theory of relativity was wrong


find variation of velocity of light in different moving frames


94. A satellite of mass M is launched into a circular orbit of radius R and time period T. A
4. second satellite of mass 0.75 M is launched into an orbit of radius 3R. The time period of
the second satellite is given by

T 1.54 T


0.65 T 0.75 T


95. A spherical ball of density p is dropped in a liquid of density . Initial acceleration of the body will be
gl4 gl2
3g14 g
96. Water flows through a long horizontal lUbe having cross -sections A I and A2 at the two end points. If the pressures at the two end points are which of the following statements is true
PI> Pz if AI> Az

P j <P2 ifAI >Az


always PI =Pz


None of the above statements is true


97. Bernoulli's theorem is based on conservation of

mass energy


momentum angular momentum


BAC-50 17 Series-B
98. A sitlf wire has a fundamental frequency of 444 Hz and gives 6 beats with a second identical wire when the tension of the second wire is slightly increased. If the tension of the first wire is the tension in the second wire is given by
450 444
444T 450T


99. An organ pipe resonating in the fundamental mode produces sound of frequency 56 Hz in air. The new frequency of the gas when filled with a gas of density 0.83 kg/m2 will be

256 Hz 307 Hz


336 Hz Cd) 353 Hz


100. Rain drops falling on the earth from high clouds reach under the influence of gravity. Just before reaching the earth the velocity of the drops

is decreasing with time


is increasing with time


is uniform for all sizes of rain drops


is uniform but is different for different drops depending on the size of the drop


101. In Poisseuille's method of measuring the viscosity, the physical quantity which needs to be measured with maximum accuracy is

pressure difference at the ends of capillary tube


volume of liquid collected


length of capillary tube


inner radius of the capillary tube


102. The viscosity is a property of liquids by virtue of which
liquid molecules attract each other
liquid becomes a good conductor of heat
liquid becomes a good conductor of electricity
Cd) liquids oppose relative motion between its parts

Serles-B 18 BAC-SO
103. Water is flowing in a pipe whose inside diameter tapers from 20 mm to 10 mm. The speed of the water at one of end points, where the diameter is 20 mm, is 0.2 ms-I. The speed of the water at the other end point will be I

0.4 ms-I 0.2 ms-1


0.1 ms-J 0.05 ms-1


104. A lamp hangs vertically from a cord in a descending lift having a retardation of 5.2 ms-2. If the tension in the cord is 36 mass of the lamp will be
2 kg 1kg
4.9 kg 9.8 kg
105. A train moving with speed of 72 km!h crosses another train moving with speed of 54 kmIh. The first train sounds a whistle of frequency 600 Hz. The change in frequency of the whistle, as heard by a person in the second train when the two trains cross each other, is approximately given by (velocity of sound in air is 340 mls)

increase by 120 Hz


decrease by 120 Hz


increase in frequency by 350 Hz


decrease in frequency by 350 Hz


106. A cylinder of radius R length L and density P floats upright in a fluid of density If it is given a small downward displacement of amplitude the time period of resulting (undamped) oscillations is
.21t 21t­

pg 'j{2Ipog

21t pXo
pg
107. The life time of meson is 2 x 10-6 S. A beam of mesons comes out from a cyclotron with velocity 0.8 where c is the velocity of light. The mean life of mesons as observed
in the laboratory will be
4 x 10-6 sec 3 x 10-6 sec
0.3 x 10-6 sec 0.25 x 10-6 sec

BAC-50 19 Series·B
108. An air -craft executes a horizontal loop of radius 1 kIn with a steady speed of 900 km!hr. The ratio of the horizontal acceleration of the air -craft to the acceleration due to gravity is

6 7
109. A stone of mass m is tied to one end of a string and revolves in a vertical circle of radius R. The net force acting on the stone at the highest point A and the lowest point B of the circle along the vertically downward direction are

FA=mg+TI ;FB=mg-T2


FA=mg-TJ ;FB =mg+T2



where VI and v2 are the velocities at the two points A and B respectively.
110. A spherical body of mass m and radius R falls in earth's gravitational field from a height h. Assuming force due air friction to be kv2, where k is a constant and v the velocity of the body, the tenninal velocity of the body is given by







111. Two point masses M and 3M are attached to the two ends of a spring having spring constant
k. The period of oscillations of this system is
k
Ipu'I"III.IPPOQIII.loRl'tI
m 3m


Series·B 20 BAC·50
112. A rigid body consists of a thin hoop of mass m and radius 0.15 m with two thin rods attached as shown in the figure each rod has mass m and length 2.0 R. The body can rotate about a horizontal axis in the plane of the hoop passing through its centre. The moment of inertia of the body about its axis of rotation is
Rod A
L
L




5.83mRz 4.83m RZ


4.53m RZ 4.33m RZ


113. The points SI and Sz are two foci of an elliptical reflector. A point source is placed at All rays emanating from the point S 1 will pass through Sz after undergoing a reflection. The time taken by each ray in reaching Sz will be

minimum maximum


stationary zero


114. A system of two thin convex lenses of focal lengths 30 em and 20 em are separated by a distance of 10 em in air. The position of unit planes are at

3emand2em 3emand -2em


7.5emand5em 7.5emand -5em


115. The system matrix elements of a lens are an =0.25, alZ =0.025, aZI and azz =0.20. The focal length of the lens is

4em 5em


25 em 40 em


116. Two lenses made of glasses having dispersive powers in the ratio 1:3 are used to make an achromatic doublet of focal length 30 em. The focal lengths of the lenses are

20emand60em 20emand-60em


30emand60em 30emand-60em


BAC·50 21 Series-B
117. Which of the following aberrations is/are minimized in the Huygen's eye-piece?

Only spherical


Only chromatic


Only coma


Both spherical and chromatic


118. Haidinger's fringes are obtained in

Michelson's interferometer


Newton's rings experiment with a convex surface on a plane glass plate


Biprism experiment


Young's double slit experiment


119. Following statements are given about interference experiments:
A. In Michelson's interferometer fringe system, the radius of circular fringes increases as the order of interference decreases.
B. In Michelson's interferometer fringe system, the radius of circular fringes decreases as the order of interference decreases.
C. In Newton's rings, the order of interference increases as the radius of circular fringes increases.
D. In Newton's rings, the order of interference increases as the radius of circular fringes decreases.
The correct option is

AandD AandB


B andC A andC .


120. If the source of light used in the Young's double slit experiment change from yellow to blue,

fringes will become wider


consecutive fringes will go farther


consecutive fringes will come closer


fringes will disappear


Serles-B 22 BAC·50
Space For Rough Work
BAC·SO 23 Serleo-B