Exam Details
| Subject | atomic, nuclear physics—i and solid-state physics—i | |
| Paper | ||
| Exam / Course | physics | |
| Department | ||
| Organization | Mizoram University | |
| Position | ||
| Exam Date | 2018 | |
| City, State | mizoram, |
Question Paper
PHY/IV/04 Student's Copy
2 0 1 8
Pre-CBCS
4th Semester
PHYSICS
FOURTH PAPER
Atomic, Nuclear Physics—I and Solid-state Physics—I
Revised
Full Marks 55
Time 2½ hours
PART A—OBJECTIVE
Marks 20
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 5
Tick the correct answer in the brackets provided 1×5=5
1. The lines in the Lyman series lie in
ultraviolet region
infrared radiation
visible region
far infrared region
2. Which type of radiation can be stopped by a sheet of paper?
Alpha particles
Beta particles
Gamma rays
X-rays
/407 1 Contd.
3. The number of atoms per unit simple cubic cell is
3
2
1
0
4. Example of ionic crystal is
SiC
diamond
solid argon
LiF
5. The average kinetic energy in the ground state in one dimension is
13
Fermi energy
1
2 Fermi energy
1
4 Fermi energy
equal to Fermi energy
SECTION—B
Marks 15
Answer the following questions 3×5=15
1. State at least three properties of positive rays.
2. Discuss radioactive carbon dating.
3. What do you mean by primitive cell?
4. Determine the Madelung constant for NaCl.
5. What do you mean by conduction electrons?
PHY/IV/04 2 Contd.
PART B—DESCRIPTIVE
Marks 35
The figures in the margin indicate full marks for the questions
1. Describe the construction, theory and working of Aston's mass
spectrograph. Write its advantages and limitations. 5
A positive charge ion beam moving along the X axis enters a region
in which there is an electric field Ey 3 ´103 V/m and the magnetic
field Bz 0·1 Wb/m2. Deduce the speed of those ions which may pass
undeflected through the region. 2
OR
State and explain Compton effect with suitable diagram. 4
A sodium surface with a work function 2·28 eV is illuminated by a
light of wavelength 400 nm. Find the kinetic energy and speed of the
photo-electrons emitted. 3
2. Deduce the law of radioactive disintegration. Derive the expressions for
mean life and half-life of a radioactive substance. 4
Write the properties of alpha and beta particles. 3
OR
What do you know about nuclear binding energy and packing fraction? 2
Show that the density of all nuclei is independent of mass number. 2
Calculate the binding energy per nucleon of helium nucleus. Given—
Mass of helium nucleus 4·00276 amu
mp 1·00728; mn 1·00867; 1 amu 931 MeV 3
PHY/IV/04 3 Contd.
3. What are crystals? Distinguish between crystalline and amorphous
solids. 3
Find an expression for density of crystalline material in terms of lattice
constants for a cubic lattice. 4
OR
Explain the crystal structure of sodium chloride (NaCl). Draw a sketch
of sodium chloride lattice and write down the coordinates of the atom
in the cell. 5
What do you mean by Miller indices and atomic packing factor? 2
4. Deduce Laue equations and hence derive Bragg's law of X-ray
diffraction. 5
How does the Laue approach differ from the Bragg's approach? 2
OR
What do you know about ionic crystals? Explain ionic bonding and
write its properties. 5
Give the relationship between direct and reciprocal lattices. 2
5. Write the assumptions of Debye model of lattice specific heat. Obtain
Debye T 3 law. 5
Discuss the success and failures of Einstein's theory of specific heat. 2
OR
State and explain Wiedemann-Franz law. 2
Obtain the expression for thermal conductivity of metal based on
classical free electron theory. 5
2 0 1 8
Pre-CBCS
4th Semester
PHYSICS
FOURTH PAPER
Atomic, Nuclear Physics—I and Solid-state Physics—I
Revised
Full Marks 55
Time 2½ hours
PART A—OBJECTIVE
Marks 20
The figures in the margin indicate full marks for the questions
SECTION—A
Marks 5
Tick the correct answer in the brackets provided 1×5=5
1. The lines in the Lyman series lie in
ultraviolet region
infrared radiation
visible region
far infrared region
2. Which type of radiation can be stopped by a sheet of paper?
Alpha particles
Beta particles
Gamma rays
X-rays
/407 1 Contd.
3. The number of atoms per unit simple cubic cell is
3
2
1
0
4. Example of ionic crystal is
SiC
diamond
solid argon
LiF
5. The average kinetic energy in the ground state in one dimension is
13
Fermi energy
1
2 Fermi energy
1
4 Fermi energy
equal to Fermi energy
SECTION—B
Marks 15
Answer the following questions 3×5=15
1. State at least three properties of positive rays.
2. Discuss radioactive carbon dating.
3. What do you mean by primitive cell?
4. Determine the Madelung constant for NaCl.
5. What do you mean by conduction electrons?
PHY/IV/04 2 Contd.
PART B—DESCRIPTIVE
Marks 35
The figures in the margin indicate full marks for the questions
1. Describe the construction, theory and working of Aston's mass
spectrograph. Write its advantages and limitations. 5
A positive charge ion beam moving along the X axis enters a region
in which there is an electric field Ey 3 ´103 V/m and the magnetic
field Bz 0·1 Wb/m2. Deduce the speed of those ions which may pass
undeflected through the region. 2
OR
State and explain Compton effect with suitable diagram. 4
A sodium surface with a work function 2·28 eV is illuminated by a
light of wavelength 400 nm. Find the kinetic energy and speed of the
photo-electrons emitted. 3
2. Deduce the law of radioactive disintegration. Derive the expressions for
mean life and half-life of a radioactive substance. 4
Write the properties of alpha and beta particles. 3
OR
What do you know about nuclear binding energy and packing fraction? 2
Show that the density of all nuclei is independent of mass number. 2
Calculate the binding energy per nucleon of helium nucleus. Given—
Mass of helium nucleus 4·00276 amu
mp 1·00728; mn 1·00867; 1 amu 931 MeV 3
PHY/IV/04 3 Contd.
3. What are crystals? Distinguish between crystalline and amorphous
solids. 3
Find an expression for density of crystalline material in terms of lattice
constants for a cubic lattice. 4
OR
Explain the crystal structure of sodium chloride (NaCl). Draw a sketch
of sodium chloride lattice and write down the coordinates of the atom
in the cell. 5
What do you mean by Miller indices and atomic packing factor? 2
4. Deduce Laue equations and hence derive Bragg's law of X-ray
diffraction. 5
How does the Laue approach differ from the Bragg's approach? 2
OR
What do you know about ionic crystals? Explain ionic bonding and
write its properties. 5
Give the relationship between direct and reciprocal lattices. 2
5. Write the assumptions of Debye model of lattice specific heat. Obtain
Debye T 3 law. 5
Discuss the success and failures of Einstein's theory of specific heat. 2
OR
State and explain Wiedemann-Franz law. 2
Obtain the expression for thermal conductivity of metal based on
classical free electron theory. 5