物理sub模拟练习题3.pdf

全真题三 1 1 Which of the following measure the charge of an election independently of its mass A Millikan oil drop experiment B Thomson experiment C Franck Hertz experiment D Cyclotron resonance E Compton effect 2 The longest wavelength x ray that can undergo Bragg diffraction in a crystal for a given family of planes of spacing d is A 4 d B 2 d C d D 2d E 4d Questions 3 4 q R1 R2 A conducting sphere of radius R2 has a cocentric spherical cavity of radius R1 as shown above The sphere has no charge However there is a charge q in the center of the cavity 3 What is the surface charge density on the inner surface of the sphere A 2 1 4 R q B 2 1 8 R q C 2 2 4 R q D 2 8 R q E 3 1 2 2 4 R qR 4 What is the potential of the sphere Assume that the potential is zero at an infinite distance away A 1 R q B 2 R q C 2 1 R qR D 1 2 R qR E 11 21 RR q 5 A person standing on the surface of the Earth throws a ball The ball leaves the thrower s hand with initial velocity vi and has final velocity vf just before it is caught If air resistance is negligible which of the following diagrams correctly represents a possible sequence of velocity vectors for the ball 全真题三 2 Vertical Horizontal Vertical Horizontal Vertical Horizontal Vertical Horizontal Vertical Horizontal A B C D E m h 6 As shown above a block of mass m is released from rest at a distance h above a vertical massless spring with spring constant k what is the maximum kinetic energy of the block A mgh B k gm mgh 22 4 1 C k gm mgh 22 2 1 D k gm mgh 22 E 2mgh M vm vB 0 BeforeAfter 7 A bullet of mass m travelling at speed v stricks a block of mass M initially at rest and is embedded in it as shown above How far will the block with the bullet embedded in it slide on a rough horizontal surface of coefficient of kinetic friction k before it comes to rest A 2 2 g v m Mm k B 2 2 g v M Mm k 全真题三 3 C 2 2 2 g v M Mm k D 2 2 g v Mm m k E 2 2 2 g v Mm m k e1e2 8 In the circuit illustrated above the point marked e1 is raised instaneously at time t0 from zero to a fixed positive potential If e2 is connected to a high impedance D C oscilloscope input the gragh of its voltage V as a function of time t will most resemble which of the following tt tt VV OO OO VV V Ot t0t0 t0t0 t0 A B C D E b c i i P r a 9 a coaxial cable having radii a b andc carries equal and opposite currents of magnitude i on the inner and outer conductors What is the magnitude of the magnetic induction at point P outside of the cable at a distance r from the axis A Zero B 2 0 2 a ir C r i 2 0 D 22 22 0 2bc rc r i E 22 22 0 2bc br r i 10 In a hologram a photographic plate contains a wave pattern that produces a three dimensional picture when illuminated with monochromatic coherent light from a laser When only half of the photographic plate is illuminated which of the following is true of the resulting picture A Only half of the picture is seen B The picture is still seen but is less distinct than before C The picture is still seen but is smaller than before D The color of the picture is changed E The picture is inverted 全真题三 4 11 Waves on a string propagate with a speed v and are represented by giving the displacement y as a function of x and t Which of the following is NOT a possible wave or pulse c b and k are constants A 2 vtxb acy B sin 2 vtxkacy vtxb C cos vtxkay D 22 vtbbx eaey E cosh vtxbay 12 A converging lens of focal length 4 centimeters is used as a magnifier If an object is place 3 centimeters from the lens what is the magnification A 3 B 4 C 6 D 12 E 24 Questions 13 14 The Maxwell distribution of molecular speeds in a gas is given by kTmv eAvvn 2 2 2 where A is constant 13 The most probable speed is A m kT2 B m kT3 C m kT8 D kT 2 3 E mkT 2 14 The root mean square speed is A m kT2 B m kT3 C m kT8 D kT 2 3 E mkT 2 15 The number of wave distribution N distinguishable molecules in K states with N1 in state 1 N2 in state 2 etc is A k i iii NNNNNN 1 lnln B 1 21 k NNN C k k NNNN 3 3 2 21 D 21k NNNN E 21 NNNN k 16 An engine absorbs heat at a temperature of 727 C and exhausts heat at a temperature of 527 C if the engine operates at maximum possible efficiency for 2000 joules of heat input the amounte of work the engine performs is most nearly A 400 J B 1450 J C 1600 J D 2000 J E 2760 J 17 The outputs of two electrical oscillators are compared by the Lissajous figures on an oscilloscope 全真题三 5 sreen The oscilloscope spot is initially at the center of the screen Oscillator Y is connected to the vertical terminals of the oscilloscope and oscillator X to the horizontal terminals Which of the following patterns could appear on the oscilloscope screen if the frequency of oscillator Y is twice that of oscillator X A B C D E Foward Voltage V Foward Current I O a bc d e 18 A tunnel diode is to be used in an oscillator to obtain microwave frequencies On the I versus V characteristic curve for the tunnels diode shown above the appropriate operating point is point A a B b C c D d E e 19 The resolving time of a counter is 2 5 10 6 second and the dead time of the recording device is 3 10 4 second If the recording number of incident particles is N 5 103 per second the number of recorded particles is closest to A 1 103 pulses s 1 B 2 103 pulses s 1 C 3 103 pulses s 1 D 4 103 pulses s 1 E 5 103 pulses s 1 20 A machine gun fires bullets of mass 20 grams each at a rate of 1200 bullets per minute The bullets hit a thick wooden target at a speed of 600 meters per second and are stopped in the target The average force exerted on the target by the bullets striking it is A 144N B 240N C 14 4 103 N D 24 0 103 N E 14 4 103 N Questions 21 22 R M r A uniform cylindrical puck of radius r and mass M is attached to the end of a cord that passes through a 全真题三 6 hole in a fixed horizontal frictionless table as shown above The center of the puck moves in a circle of radius R with angular speed 21 The magnitude of the angular momentum of the puck about the hole is A 2 2 3 RM B 22 rRM C 2 2 1 22 rRM D 2 1 22 rRM E 2 2 1 22 2 1 rRM 22 If the string is pulled slowly downward so that the center of the puck moves in a circle of smaller radius quantities that are conserved include which of the following I Angular momentum II Linear momentum III Kinetic energy A I only B III only C I and II only D II and III only E I II and III F f 23 The Fermi distribution function f for elections in a metal is shown above Which of the following statements is true for this metal A The Fermi energy F is of the order of kT B The spread in energies is independent of the temperature C The higher the density of elections the lower the Fermi level D The distribution results from the assumption that any number of elections can occupy a given quantum state E Only those elections which kT of the Fermi level can be excited Thermally 24 Solid argon is held together by which of the following bonding mechanism A Ionic bond only B Covalent bond only C Partly covalent and partly ionic bond D Metallic bond E van der Waals bond 25 A metal surface emits photoelectrons with maximum energy 1 0 electron volt eV when illuminated by 2 0 eV photons When the surface is illuminated by 4 0 eV photons the maximum energy of the photoelectrons is A 0eV B 2 0eV C 3 0eV D 4 0eV E 5 0eV 26 Which of the following values of the atomic number Z corresponds to an atom with valence 2 A 6 B 12 C 14 D 18 E 32 27 A muon is a heavy electron with a mass about 200 times of a hydrogen atom is E0 the binding energy of a muon proton atom is most nearly A E0 B 14 E0 C 200 E0 D 4000 E0 E 40 000 E0 全真题三 7 Questions 28 29 In an inertial frame S a particle has a momentum Px Py Pz 5 3 2 MeV c and a total energy 10 MeV 28 The speed u of the particle as measured in a frame S is most nearly A c 8 3 B c 5 2 C c 2 1 D c 5 3 E c 5 4 29 Which of the following combinations of momentm p and energy E could represent the motion of the particle described above as observed in another inertial frame S moving with an unspecified velocity v relative to s A MeV c8 0 0 p MeV128 E B MeV c2 0 8 p MeV10 E C MeV c6 4 31 p MeV949 E D MeV c200 30 50 p MeV100 E E MeV c0 10 100 p MeV000 10 E 30 An expression for the potential energy of two ions is 9 2 r b r kq EP What is the constant b as a function of the equilibium spacing r0 A 10 0 2 r kq B 0 2 r kq C 0 2 9 8 r kq D 10 0 2r kq E 9 8 0 2r kq 31 In a 2S state of the helium of the possible values of the total electronic angular momentum are A 0 only B 1 only C 0 and 1 only D 0 1 2 and 1 E 0 1 and 2 Questions 32 33 3 0 V 50 50 60 30 30 R1 R2 R3R4 R5 In the circuit shown above the resistances are given in ohms and the battery is assumed ideal with emf equal to 3 0 volts 32 The resistor that dissipates the most power is A R1 B R2 全真题三 8 C R3 D R4 E R5 33 The voltage across resistor R4 is A 0 4 V B 0 6 V C 1 2 V D 1 5 V E 3 0 V 34 A conducting cavity is driven as an electromagnetic resonator If perfect conductivity is assumed the transverse and normal field components must obey which of the following conditions at the inner cavity walls A En 0 Bn 0 B En 0 Bt 0 C Et 0 Bt 0 D Et 0 Bn 0 E None of the above Questions 35 36 Light of wavelength 5200 Angstroms is incident normally on a transmission diffraction grating with 2000 lines per centimeter 35 The first order diffraction maximum is at an angle with respect to the incident beam that is most nearly A 3 B 6 C 9 D 12 E 15 36 The grating is ruled over a width of 10 centimeters If it is well made the closest soublet line at about 5000 Angstroms that the grating can resolve in first order has a seperation of most nearly A 0 0025 A B 0 025 A C 0 25 A D 2 5 A E 25 A 37 Ten measurements are made of a certain physical quantity The numerical values obtained are 4 6 7 3 5 8 2 5 and 5 Which of the following statements is NOT correct A The mean value of the measurements is 5 B The median value of the measurements is 5 C The modal value of the measurements is 5 D The experimental stanard rms deviation is approximately 1 7 E If the universe from which the sample is drawn has a Gasussian distribution with standard rms deviation of 1 7 the probability is 0 5 that the next measurement will lie in the range 3 3 to 6 7 38 Which of the following is most commonly used to provide a stable reference voltage of about 12 volts in an electronic circuit A Zener diode B Tunnel diode C Thynstor D Vanstor E Field effect transistor 39 Which of the following is NOT an attribute of a typical photomultiplier tube A It operates by producing an avalanche of ions in a gas B It can produce electrical output less than 10 6 second long C It can produce 105 or more electrons per incident photon D Is is affected by ambient magnetic fields greater than a few gauss E It detects photoelectrons ejected by light from a photocathode 40 A rigid cylinder rolls at constant speed without slipping on top of a horizontal plane surface The acceleration of a point on the circumference of the cylinder at moment when the point touches the plane is A directed forward B directed backward 全真题三 9 C directed up D directed E zero Questions 41 42 A cylinder with moment of inertia 4 kg m2 about a fixed axis initially rotates at 80 radians per second about this axis A constant torque as applied to slow it down to 40 radius per second 41 The kinetic energy lost by the cylinder is A 80 J B 800 J C 4000 J D 9600 J E 19 200 J 42 If the cylinder takes 10 seconds to reach 40 radius per second the magnitude of the applied torque is A 80 N m B 40 N m C 32 N m D 16 N m E 8 N m Questions 43 44 A nonrelativistic particle of mass m moves in a plane Its position is described by the polar coordinates r and with time derivatives r and There exists a potential energy U kr2 where k is a constant 43 Which of the following is the Lagrangian of the particle A 2222 2 1 krrrmL B 222 2 1 krrmL C 22222 2 1 krrrmL D 2222 2 1 krrr rrmL E 2222 2 2 1 krrr rrmL 44 Which of the following quantities remains constant A 222 rrm B 22 mr C 2 kr D mr E 2 mr 45 A ball dropped from a height h As it bounces off the floor its speed is 80 percent of what it was just before it hit the floor The ball will then rise to a height of most nearly A 0 94 h B 0 80 h C 0 75 h D 0 64 h E 0 50 h m1m2 x 46 Two masses m1 and m2 are joined by a msaaless spring of force constant k and placed on a horizontal frictionless surface as shown above The system is released from rest when the separation between the masses is x If the unstretched length of the spring is x0 the speed of mass m1 when the two masses are a distance x0 apart is A 2 0 1 xx m k B 2 0 2 xx m k C 2 0 21 xx mm k 全真题三 10 D 2 0 21 2 1 xx mm m m k E 2 0 21 1 2 xx mm m m k 47 The anomalous Zeeman effect results from A a nonuniform applied magnetic field B more than one isotope being present C a magnetic moment arising from electron spin D a nuclear quadrupole moment E forbidden atomic transitions 48 In a Compton scattering experiment a collimated beam of monochromatic x rays of wavelength 0 7 angstrom impinges on a small cylindrical carbon scatter The scattered radiation is investigated as a function of the angle between it and the primary bean The scattered radiation contains A no wavelength other than that of the primary beam B a component shifted in wavelength by an amount that is independent of the wavelength of the primary beam C a component shifted in wavelength by an amount that is independent of the scattering angle D a component shifted in wavelength by an amount that decreases as the scattering angle increases E two components with wavelength shifted up and down by equal amounts 49 Stern and Gerlach succeeded in deflecting a beam of silver atoms with an inhomogeneous magnetic field Which of the following is a generally accepted inference from the results of their measurements A The technique is useful for precise measurement of magnetic field intensities B The single deflection observed is principally due to induced magnetic moment in the silver atom C The two deflections observed are due to the two possible measured values of a component of the magnetic moment of the atom D The three deflections observed are due to neutral atoms negatively charged ions and positively charged ions E The continuous range of values observed is due to random orientation of the magnetic moments of the atoms x V O x1 V0 x2 50 An attractive one dimensional square well has depth V0 as shown above If there is a bound state at an energy 0 which of the following best shows a possible wave function for this state 全真题三 11 x O x1x2 x O x1x2 x O x1x2 x O x1x2 x O x1x2 A B C D E 51 If an electron were confined to nuclear dimensions the uncertainty in its momentum would be most nearly A 0 2 eV c B 200 eV c C 200 KeV c D 200 MeV c E 200 GeV c 52 Which of the following statements about the lattice vibrations of a crystal of NaCl is NOT true A The acoustic modes for long wavelengths correspond to elastic waves B In the acoustic mode the Na and Cl ions tend to move in the same direction C For each value of the propagation vector k there is one transverse acoustic mode and one longitudinal acoustic mode D In the optical mode the Na and Cl ions move in opposite directions E The optical mode has an oscillatory dipole moment 53 Conduction electrons is an elemental semiconductor such as germanium and silicon can be produced by all of the following means EXCEPT A thermal excitation B optical excitation C electron injection in a junction D doping with a group III element E doping with a group V element 54 If f is frequency and h is Planck s constant the zero point energy of a one dimensional quantum mechanical harmonic oscillator is A 0 B hf 3 1 C hf 2 1 D hf E hf 2 3 Questions 55 56 Two spin 2 1 particles 1 and 2 have spins in a singlet state with spin wave function 1 2 2 1 2 1 2 1 where and refer to up and down spins respectively along any chosen axis The spin of particle 1 is measured along the z axis and found to be up 55 A simultaneous measurement of the spin of particle 2 along the z axis would yield which of the 全真题三 12 following results A Up with 100 probability B Down with 100 probability C Up with 25 probability down with 75 probability D Up with 50 probability down with 50 probability E Up with 75 probability down with 25 probability 56 A simultaneous measurement of the spin of particle 2 along the x axis would yield which of the following results A Up with 100 probability B Down with 100 probability C Up with 25 probability down with 75 probability D Up with 50 probability down with 50 probability E Up with 75 probability down with 25 probability A B 57 A uniform and constant magnetic field B is directed perpendicularly into the plane of the page everywhere within a rectangular region as shown above A wire circuit in the shape of a semicircle is rotated counterclockwise in the plane of the page about an axis A The axis A is perpendicular to the page at the edge of the field and directed through the center of the straight line portion of the circuit Which of the following graphs best approximates the emf induced in the circuit as a function of time t tO A tO B tO C tO D tO E X Y P Q 全真题三 13 58 The diagram above represents the electric field and the equipotential line for two charged conductors X and Y The charge on X is positive Which of the following statements is NOT correct A The charges on X and Y are of the same sign B The charge on X is greater than that on Y C The electric field lines and the equipotential lines always intersect each other at an angle of 90 degrees D A test charge placed at point P would be in equilibrium under the action of the electrical forces E The electrical potential at point P is less than it is at point Q which is symmetrically located on the other side of X 59 The potential difference across the terminals of a battery is 10 volts if no current is drawn from it When a 4 ohm resistor is connected across the terminals a current of 2 amperes is drawn from the battery This resistor is then removed and replaced with a variable resistor that can have any value of