7 đề thi vật lý 2 Đại học Bách khoa TPHCM chương trình dạy bằng tiếng anh

chỉ cần ôn 7 đề này chắc chắn sẽ trên 9đ môn vật lý 2 hoặc sẽ giúp bạn qua môn 1 cách dễ dàng mà không cần ôn luyện quá nhiều, tài liệu này là tài liệu trong danh sách ngân hàng đề thi của đại học Bách Khoa

Code 138 / Page 1 of 4

NATIONAL UNIVERSITY – HO CHI MINH CITY

UNIVERSITY OF TECHNOLOGY

DEPARTMENT OF ENGINEERING PHYSICS

FINAL EXAM OF PHYSICS A2 SEMESTER 1, YEAR 2015-2016

Closed book exam – Duration: 120 min Code: 138

Student’s name:………

Student ID: ………

Signature of Lecturer: ………

Signature of Dean: ………

01 ; / = ~ 06 ; / = ~ 11 ; / = ~ 16 ; / = ~ 02 ; / = ~ 07 ; / = ~ 12 ; / = ~ 17 ; / = ~ 03 ; / = ~ 08 ; / = ~ 13 ; / = ~ 18 ; / = ~ 04 ; / = ~ 09 ; / = ~ 14 ; / = ~ 19 ; / = ~ 05 ; / = ~ 10 ; / = ~ 15 ; / = ~ 20 ; / = ~

PART 1 MULTIPLE CHOICE QUESTIONS Question 1 In the Zeeman effect, the following selection rules are applied: A. 1;m1 B.1;m0,1 C. 01;m1 D. 01;m0,1 Question 2 In order of increasing strength the four basic interactions are: A. gravitational, weak, electromagnetic, and strong

B. weak, gravitational, electromagnetic, and strong C. weak, electromagnetic, gravitational, and strong D. gravitational, electromagnetic, weak, and strong Question 3 For valence electrons in atoms of sodium Na (Z=11), while taking into account of the spin, electrons can make the transition to energy level 32D3/2 from the following energy levels: A. n2P1/2( n  4 , 5 , 6 ); n2P3/2( n  4 , 5 , 6 ); n2F7/2( n  4 , 5 , 6 )

B. n2P1/2( n  4 , 5 , 6 ); n2P3/2( n  4 , 5 , 6 ); n2F5/2( n  3 , 5 , 6 )

C. n2P1/2(n4,5,6 );n2P3/2(n4,5,6 );n2F5/2(n4,5,6 )

D. n2P1/2(n4,5,6 );n2P3/2(n4,5,6 );n2F7/2(n3,5,6 )

Question 4 Electromagnetic radiation with a wavelength of 5.7×10−12m is incident on stationary

electrons Radiation that has a wavelength of 6.57×10−12 m is detected at a scattering angle of:

Question 5 A particle in an infinite potential energy well of width a The particle is at the state of n=5

The probability of finding particle in the region [a/10, 4a/5] is:

Question 6 When a hydrogen atom makes the transition from the third excited state to the ground state

(at−13.6 eV) the energy of the photon emitted is:

Question 7 Given Ro=1.2fm The radius of 2965Cunucleus is :

Question 8 The quark content of a proton is:

Code 138 / Page 2 of 4

Question 9. A particle is confined by finite potential energy walls to a one-dimensional trap from x=0 to

x=L Its wave function in the region x<0 has the form (with k is positive):

A. ψ(x)=0 B. ψ(x)=Aexp(−kx) C. ψ(x)=Asin(kx) D. ψ(x)=Aexp(kx)

Question 10 A meter stick moves in the direction of its length through a laboratory According to

measurements taken in the laboratory, its length is 0.4 m The speed of the meter stick relative to the laboratory is:

Question 11 A measurement of the length of an object that is moving relative to the laboratory consists

of noting the coordinates of the front and back:

A. at the same time according to clocks that move with the object

B. at different times according to clocks at rest in the laboratory

C. at the same time according to clocks at rest with respect to the fixed stars

D. at the same time according to clocks at rest in the laboratory

Question 12 Which of the following particles has a lepton number of zero?

Question 14 The significance of ||2 is:

A. energy density B. energy C. probability density D. probability

Question 15.An electron is in a quantum state for which there are seven allowed values of the z

component of the angular momentum The magnitude of the angular momentum is:

Question 16 Two events occur simultaneously on the x axis of reference frame S, one at x=−a and the

other at x=+a According to an observer moving in the negative x direction:

A. the event at x=−a occurs first

B. the event at x=+ a occurs first

C. the events are simultaneous

D. either event might occur first, depending on the value of a and the observer's speed

Question 17. The Balmer series of hydrogen is important because it:

A. is the only series that occurs for hydrogen

B. is the only one for which the quantum theory can be used

C. involves the lowest possible quantum number n

D. is in the visible region

Question 18 To a good approximation, the sun's surface is a blackbody with a surface temperature of

5800 K The wavelength at which the sun emit most strongly is

a) The probability that the electron will be found in the volume dV bounded by a

spherical shell of radius r and r+dr

b) The probability that the electron will be found in the volume V from r=0 to r=a from the nucleus? b) What is the probability that the electron will be found in a region from r=0 to r= from the nucleus? Where a = 0.53x10-10m

Problem 2

Find the total binding energy and the binding energy per nucleon of 19779Au The neutral atomic mass of

Au

197

79 is 196.966569 u The mass of neutron is mn=1.008665u, the mass of Hydrogen atom is

mH=1.007825u The atomic mass 1u=931.5MeV/c2

Problem 3

A proton and an antiproton annihilate, producing two photons Find the energy, and wavelength of each photon

(a) if the p and p are initially at rest and

(b) if the p and p collide head-on, each with an initial kinetic energy of 900 MeV

Some physical constants

Stefan-Boltzmann constant: =5,67.10-8 W/(m2K4)

Compton wavelength of electron: o=2,426.10-12 (m)

m2

Code 138 / Page 4 of 4

1/2

National University – Ho Chi Minh City

University of Technology

Department of Engineering Physics

FINAL EXAM OF PHYSICS A2 – SEMESTER 183

Closed book exam – Duration: 90 min No 2

A) (L.O.1, L.O.2) MCQ ANSWER SHEET: (4 POINTS)

Choose for each question only one correct answer and darken corresponding circle in the following answer sheet

A Stays the same B Factor of ¼ C Factor of ½ D Factor of 2

2 Neodymium 144 Nd is a nuclide that undergoes alpha decay The nuclide that is the product of the decay is

A 0.42 rad B 2.32 rad C 0.62 rad D 1.08 rad

5 Electromagnetic radiation with 0.75 MeV of energy is scattered from stationary electrons The scattered photons have wavelength equal to Compton wavelength Through what angle were the photons scattered?

A 0.54 rad B 2.46 rad C 3.21 rad D 0.82 rad

6 The concentration of photons in a uniform light beam with a wavelength of 500nm is 1.7 × 10 13 m −3 The intensity of the beam is:

A 6.7 × 10−6 W/m2 B 1.0 × 103 W/m2 C 2.0 × 103 W/m2 D 4.0 × 103W/m2

7 Which of the following electromagnetic radiations has photons with the greatest energy?

A blue light B yellow light C x rays D radio waves

8 Which of the following (n, l, m , ms) combinations is impossible for an electron in an atom?

A 3, 1, 1, −1/2 B 6,2,0,1/2 C 3, 2, −2, −1/2 D 3, 1, −2, 1/2

9 Which particle has the smallest rest energy?

A A neutron B An electron C An ion D A proton

10 The electron microscope is a welcome addition to the field of microscopy because electrons have a wavelength than light, thereby increasing the of the microscope

A Longer; resolving power B Shorter; resolving power

C.Longer; intensity D Shorter; intensity

11 Find the excitation energy from the ground level to the third excited level for an electron confined to of an infinite square well that has a width of 0.125 nm

2/2

12 Compare the Broglie wavelength λe of an electron with the wavelength λp of a proton, if they have the same momentum

A λ e < λ p B λ e > λ p C λ e = λ p

13 An electron is in a quantum state for which there are 5 allowed values of the z component of the angular momentum The magnitude of the angular momentum

A √3ħ B √6ħ C √5ħ D √12ħ

14 A radioactive source has a half-life of 100 days If the initial activity is 1.0 mCi, what is the activity after 30 days?

A 0.14 mCi B 0.81 mCi C 0.55 mCi D 0.76 mCi

15 Protons in the nucleus attract electrons with enough electromagnetic force to keep them in orbit at high speeds Protons in general repel each other, but in the nucleus they are bound together Why ?

A The strong force binds the protons together on small distance scales

B The electrons orbiting the nucleus create an EM force on all sides due to their high speed of revolution

C The electroweak force binds the protons together on small distance scales

D The gravitational force binds the protons together on small distance scales

16 An alien spacecraft is flying overhead at a great distance as you stand in your backyard You see its searchlight blink on for 0.19s The first officer on the spacecraft measures that the searchlight is on for 12ms What is the speed of the spacecraft relative

to the earth expressed as a fraction of the speed of light c?

B PROBLEMS (L.O.1, L.O.2): (6 POINTS)

1 Energy radiated per second from 5 cm2 of the surface of a black-body is 36.75x103 J Calculate:a) The temperature of the body

3/2

b) The wavelength of the radiation emitted with the greatest intensity

Ans: T=6000K; Wavelength= 483 nm

2 An atom in a 3d state emits a photon of wavelength 475nm when it decays to a 2p state

(a) What is the energy (in eV) of the photon emitted in this transition?

(b) Find the number of allowed transitions if the atom is now in an external magnetic field of 3,5T Ignore the effects of the electron’s spin

(c) Calculate the photon energies (in eV) emitted in the case (b) Given Bohr magneton µB= 9.27x10-24 J/T

Ans: a 2,612eV; b 9 transitions; c (2.612 – 0.0002)eV; 2.612 eV; (2.612 + 0.0002)eV

3 The common isotope of uranium, 238U, has a half-life of 4.47x109 years, decaying to 234Th by alpha emission

(a) What is the decay constant?

(b) What mass of uranium is required for an activity of 1.00 Ci?

(c) How many alpha particles are emitted per second by 10.0 g of uranium?

Ans: λ=4.92x10-18, m=2.99x103kg, λN=1.24x105

Some useful constants:

s J

4/2

5/2

1

National University – Ho Chi Minh City

University of Technology

Department of Engineering Physics

FINAL EXAM OF PHYSICS A2

2018-2019 Closed book exam – Duration: 90 min

No

1

A) (L.O.1, L.O.2) MCQ ANSWER SHEET (4 pts):

Choose for each question only one correct answer and darken corresponding circle in the following answer sheet

1 Einstein’s Postulates state that …

A The laws of physics are the same in all inertial frames of reference

B The speed of light in vacuum is the same in all inertial frames of reference and is independent of the motion of the source

C A particle can travel at the speed of light in vacuum

3 An alpha particle (m = 6.64 x10-27 kg) emitted in the radioactive decay of uranium-238 has an energy

of 4.20 MeV What is its de Broglie wavelength?

4 An electron in an atom initially has an energy of -3.2 eV above the ground state energy It drops to a

state with an energy of -5.5 eV above the ground state energy and emits a photon in the process The momentum of the photon is:

A 1.2 x 10-27 kg.m/s B 1.7 x 10-27 kg.m/s C 4.3 x 10-27 kg.m/s D 2.3 x 10-27 kg.m/s

5 There are Uranium and Lead atoms in Uranium ore Lead atoms are the products of the radiation of

Uranium The half life of Uranium is 5.5×109 years How old is the ore if the ratio between the number

of Uranium and Lead atoms are 5:1:

6 Einstein suggested that:

A Light is composed of tiny particles called protons

B The speed of photon is c =3.10 m/s in free space and equal v = c/n in medium 8

C Each photon has energy ε =hc/λ, where h: Planck’s constant, λ : light wavelength

D All of the above

7 The wave function of a particle must satisfy certain feratures:

C Must be a continuous function and the first derivative also must be continuous

2

D All of the above

8 In Compton effect, the maximum kinetic energy of the emitted electrons is 3 keV What's the

wavelength of the incident light?

9 In hydrogen atom, electron is in the quantum state 2s, received any energy to get the excited state

What is the proper wave function of the excited state?

A ψ511 B ψ400 C ψ500 D ψ401

10 The binding energy of a nucleus is the energy that must be supplied to:

A bind nucleons together in nucleus B remove an alpha particle

C remove a beta particle D separate the nucleus into nucleons

11 The half-life of a radionuclide is 60 days After how many days will it decay to 0.1% of its original activity?

A 300 B 600 C 3000 D 6000

12 The formulas of non-relativistic microscopic particle momentum is:

A p = h/λ B p = (2mE)1/2 C A and B are correct D A and B are wrong

(For 02 next questions) A hydrogen atom in the 5g state is placed in a magnetic field of 0.600 T that is in

the z-direction

13 Into how many levels is this state split by the interaction of the atom’s orbital magnetic dipole

moment with the magnetic field?

14 What is the energy separation between adjacent levels?

15 Which of the following (n, l, ml, ms) combinations is possible for an electron in an atom?

16 The frequency and wavelength of the matter wave associated with a 10eV free electron are:

A 1.5 × 1034 Hz, 3.9 × 10−10 m B 1.5 × 1034 Hz, 1.3 × 10−34 m

C 2.4 × 1015 Hz, 1.2 × 10−9 m D 2.4 × 1015 Hz, 3.9 × 10−10 m

17 Which of following statements is wrong :

A ∆m=0,±1 B ∆l = ±1 C ∆j = ±1 D A and B are correct

(For 02 next questions) Two stars, both of which behave like ideal blackbodies, radiate the same total

energy per second The cooler one has a surface temperature T and a diameter 3.0 times that of the hotter

3

B PROBLEMS (L.O.1, L.O.2) :

1 (2 pts) A black-body emits the radiation with the greatest intensity wavelength 0.550 μm Calculate: a) The temperature of the body

b) The energy radiated per second from 10cm2 of the body surface

a) What is the orbital quantum number l of mentioned electron state

b) Find the possible values of L and Lz for this electron?

where b = 2.00 m-1, A>0, and the +x-axis points toward the right

a) Determine A so that the wave function is normalized

b) Find the probability of finding this particle in each of the following regions: (i) within 50.0 cm of the

origin, (ii) on the left side of the origin, (iii) between x = 0.500 m and x = 1.00 m

Sol

A = sqrt(b) = sqrt(2) m-1

Some useful constants:

s J

h=6,625.10−34 8 2 4

10.67,

s m

NATIONAL UNIVERSITY- HO CHI MINH CITY

UNIVERSITY OF TECHNOLOGY

DEPARTMENT OF ENGINEERING PHYSICS

FINAL EXAM OFPHYSICS A2 SEMESTER 2, YEAR 2015-2016

Closed book exam - Duration: 120 min Code: X.52

Qf r rrlant' Signature of Lecturer:

PART 1 MULTII'LE CIIOICE QUESTIONS (5 points)

Question 1 An electron participates in:

A the electromagnetic and gravitational forces only

B the electromagnetic, gravitational, and weak forces only

C the electromagnetic, gravitational, and strong forces only

D the strong and weak forces onlY

euestion 2.If awave function y for a particle moving along the x axis is normalized, then:

t TrYl2 dt=1

-@

_l*12

dx=1

euestion 3 A photon of wavelength 1.60 x10'12 m scatters from a free electron For what scattering angle does the iecoiling electron have kinetic energy equal to the energy of the scattered photon?

Question 4 Given \:1.2fm The radius of |flnunucleus is:

magnitude B (in Tesla) iirequired to split the 3p state into multiple levels with an energy difference

of 3.1x10-sey between adjacent levels?

8.0.64 c.0.59

Question 8 An proton moves with a speed of S.O x l06m/s Its de Broglie wavelength is

A.8.4"10-lam B I gx lo-12 m c l.gxlo-l4m D.t.ox1o-1om

euestion 9 In the Zeeman effect, when the atom is put in an external magnetic field B, how many possible transitions are there from the nD to the mP energy levels?

Question 10 Evidence for the wave nature of matter is:

A electron diffraction experiments of Davisson and Germer

B Young's double slit experiment

c Thompson's measurement of e/m

D the Compton effect

Question 11 The quark content of a molecule CO (lf c;lfro; is:

A.40u.38d 8.44u,46d C.40t.42d D 38u.40d

Question 12 Ameasurement of the length of an object that is moving relative to the laboratory

consists of noting the coordinates of the front and back:

A at the same time according to clocks that move with the object

B at the same time according to clocks at rest with respect to the fixed stars

C at the same time according to clocks at rest in the laboratory

D at different times according to clocks at rest in the laboratory

Question 13 The Heisenberg uncertainty principle for position and momentum is given by:

A All other answers are correct B l*.1px > *.L

euestion 15 Let A be the mass number and Zbethe atomic number of a nucleus Which of the

following is^approximately correct for light nuclei?

euestion 18 A particle in an infinite potential energy well of width a The particle is at the state of

n:6 The probability of finding particle in the region [a/6,3a/4]is:

D.2t3

euestion 19 To a good approximation, the sun's surface is a blackbody with a surface temperature of

6000 K The wavelength at which the sun emit most strongly is

4 ri n^-^ a ^ft

Question 20 An electron is in a one-dimensional well with finite potential energy barriers at thewalls The matter wave:

A is zero in the well B extends into the barriers

C is discontinuous at the barriers D is zero at the ba:riers

.*(x)={f;.-.'*.0 x>o

PART 2 PROBLEMS (5 points)

PROBLEM 1(2 points)

A quantum particle has a wave function

a) Find the constant A so that the wave function is normalized.

b) Find the probability of finding the particle between x:0 and x:a

PROBLEM 2 (2 points)

A spacecraft is launched from the surface of the Earth with a velocity of 0.600c at an angle of 50.0o above the horizontal positive x axis Another spacecraft is moving past with a velocity of 0.700c in the negative xdirection Find the magnitude and direction of the velocity of the first spacecraft as measured by the pilot of

the second spacecraft.

Problem 3 (1 points)

Protons are placed in a 3.50T magnetic field that points in the positive z direction.

(a) What is the energy difference between states with the z component of proton spin angular momentum parallel and antiparallel to the field.

(b) A proton can make a transition from one of these states to the other by emitting or absorbing a photon with

the appropriate energy Find the frequency and wavelength of such a photon.

Some phltsical constants

Stefan-Boltzmann constant: e5,67 I 0{ W1m2K4;

Code 152 Paee 3 of3

National University – Ho Chi Minh City

University of Technology

Department of Engineering Physics

FINAL EXAM OF PHYSICS A2

2015-2016

Closed book exam – Duration: 120 min

10.67,

s m

c3.108 / m e 9,1.1031kg e 19C

10.6,



1 Consider the photoelectric effect for platinum

which is a metal with work function 8.50 eV

What is the maximum wavelength of light λ max

that can be used to eject electrons from the metal?

A 176 nm

B 225 nm

C 145 nm

D 589 nm

2 Assuming your cellular phone operates at 850

MHz, how many photons per second correspond

to 800 mW (a typical cell phone output strength)?

[FYI: The FCC mandates less than 1.6 W per

3 In Compton effect, the wavelength of the

incident light is 413 nm What's the maximum

kinetic energy of the emitted electrons?