10/10/23, 9:18 AM Engineering physics
ENGINEERING PHYSICS – II (PH2161)
QUESTION BANK
UNIT – I – CONDUCTING MATERIALS
PART - A
1. What are conducting materials? Give examples.
2. List out the properties of metallic conductors.
3. Define electric field and electric field intensity.
4. What is meant by free electron?
5. What is meant by valance electron?
6. What are core electrons?
7. Define mean free path.
8. What is meant by electron-lattice scattering?
9. Define relaxation time and collision time.
10. Define drift velocity of electrons and give its formula.
11. What are the different between drift velocity and thermal velocity of an electron?
12. Define mobility of electrons.
13. Define current density.
14. Get the microscopic form of Ohm’s law and state whether it is true for all temperatures.
15. Discus the variation of resistivity of a conductor with respect to temperatures.
16. What are the sources of resistance in metals?
17. List out the three main theories developed for metals.
18. State the postulates of classical free electron theory.
19. Define electrical conductivity.
20. Define thermal conductivity.
21. Distinguish between electrical and thermal conductivity.
22. Write the similarities between electrical and thermal conductivities.
23. State Wiedemann – Franz Law. Give the value of Lorenz number and state whether it holds good for all
metals and at all temperatures?
24. What is Lorentz number?
25. What are the merits of classical free electron theory?
26. What are the special features of classical free electron theory of metals?
27. Mention the drawbacks of classical free electron theory.
28. State quantum theory of free electron.
29. Mention the important features of quantum free electron theory of metals.
30. What are the important applications of quantum free electron theory?
31. Aluminium has three valence electrons and copper has one valence electron. Why do we have large
electrical conductivity for copper than Aluminium?
32. What are the differences between quantum theory and zone theory?
33. Write Fermi-Dirac distribution function and give its importance.
34. Write down the expression for the Fermi Dirac distribution law and explain it for the electrons in a metal.
35. Draw the Fermi energy distribution curve at 0 K and at any temperature ‘T’K.
36. Define Fermi energy level and Fermi energy with their importance.
37. Define Fermi energy surface (or) Fermi sphere and give its importance.
38. Why is that only the electrons near the Fermi level contribute to electrical conductivity?
39. Define density of states with example. States its importance.
PART - B
40. What is meant by Fermi energy of a metal?
1. Explain classical free electron theory of metals. Give its merits and drawbacks.
2. On the basis of free electron theory. Derive an expression for the electrical and thermal conductivities of
metal and hence establish Wiedemann-Franz Law.
3. State and prove Wiedemann-Franz Law.
4. Discuss classical free electron theory of metals. Obtain the expression for electrical resistivity in terms of
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, 10/10/23, 9:18 AM Engineering physics
35. Draw the Fermi energy distribution curve at 0 K and at any temperature T K.
36. Define Fermi energy level and Fermi energy with their importance.
37. Define Fermi energy surface (or) Fermi sphere and give its importance.
38. Why is that only the electrons near the Fermi level contribute to electrical conductivity?
39. Define density of states with example. States its importance.
PART - B
40. What is meant by Fermi energy of a metal?
1. Explain classical free electron theory of metals. Give its merits and drawbacks.
2. On the basis of free electron theory. Derive an expression for the electrical and thermal conductivities of
metal and hence establish Wiedemann-Franz Law.
3. State and prove Wiedemann-Franz Law.
4. Discuss classical free electron theory of metals. Obtain the expression for electrical resistivity in terms of
well known microscope quantities. Discuss the dependence on temperature.
5. (a) What are the postulates of classical free electron theory?
(b) Derive an expression connecting electrical conductivity and relaxation time.
6. a) Deduce an expression for electrical conductivity of conducting material
b) List out the drawbacks of classical free electrons theory
7. Deduce a mathematical expression for electrical conductivity and thermal conductivity of a conducting
material and hence obtain Wiedemann-Franz Law.
8. Write Fermi-Dirac distribution function. Explain how Fermi function varies with temperature?
9. Write down the Fermi-Dirac equation for the probability of occupation of an energy level E by an electron.
Show that the probability of its occupancy by an electron is zero if E > EF and unity if E < E F at temperature
0K
10. Define density of energy states. Derive an expression for the density of energy states and carrier
concentration in a metal by using the Fermi distribution function.
11. i) Obtain an expression for the density of states for a metal.
ii) State the merits and demerits of classical free electron theory.
12. What is density of states? Derive an expression for density of states and using that obtain an expression for
Fermi energy of a metal of O K.
13. i) Define Fermi energy.
ii) Explain Fermi Dirac distribution for electrons in a metal.
iii) Obtain an expression for Fermi energy at temperature T=O and relate it to Fermi energy at non zero
temperature.
14. i) Explain the meaning of ‘density of states’. Derive an expression for the number of allowed states for unit
volume of a solid.
ii) Write an expression for the Fermi energy distribution function FD (E) and discuss its behavior with
change in temperature. Plot FD (E) versus E for T=0K, and T>0K.
15. Derive an expression for carrier concentration in a metal by using the Fermi distribution function. Explain
the variation of Fermi level with temperature.
16. i) Define Fermi energy.
ii) Explain Fermi Dirac distribution for electrons in a metal.
iii) Obtain an expression for Fermi energy at temperature = 0 K and relate it to Fermi energy at non zero
temperature.
17. Write a short notes on classical theory, Fermi – Dirac distribution, wideemann – franz law
18. Explain the dependence of electrical conductivity on temperature on impurities.
Unit – II – SEMICONDUCTING MATERIALS
PART – A
1. What are semiconductors? Give example.
2. State the properties of semiconductor.
4. 3.
What are theany
Mention types of advantages
four semiconductor?
of semiconducting materials.
5. What are intrinsic and extrinsic semiconductors? Give examples.
6. Mention the applications of extrinsic semiconductors.
7. Distinguish intrinsic and extrinsic semiconductor?
8. What is meant by doping and doping level?
9. How are n-type and p-type semi conductors produced?
10. You are given a piece of extrinsic semiconductor. How will you find to which type it belongs?
11 What is the effect of impurity states over extrinsic semiconductors?
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ENGINEERING PHYSICS – II (PH2161)
QUESTION BANK
UNIT – I – CONDUCTING MATERIALS
PART - A
1. What are conducting materials? Give examples.
2. List out the properties of metallic conductors.
3. Define electric field and electric field intensity.
4. What is meant by free electron?
5. What is meant by valance electron?
6. What are core electrons?
7. Define mean free path.
8. What is meant by electron-lattice scattering?
9. Define relaxation time and collision time.
10. Define drift velocity of electrons and give its formula.
11. What are the different between drift velocity and thermal velocity of an electron?
12. Define mobility of electrons.
13. Define current density.
14. Get the microscopic form of Ohm’s law and state whether it is true for all temperatures.
15. Discus the variation of resistivity of a conductor with respect to temperatures.
16. What are the sources of resistance in metals?
17. List out the three main theories developed for metals.
18. State the postulates of classical free electron theory.
19. Define electrical conductivity.
20. Define thermal conductivity.
21. Distinguish between electrical and thermal conductivity.
22. Write the similarities between electrical and thermal conductivities.
23. State Wiedemann – Franz Law. Give the value of Lorenz number and state whether it holds good for all
metals and at all temperatures?
24. What is Lorentz number?
25. What are the merits of classical free electron theory?
26. What are the special features of classical free electron theory of metals?
27. Mention the drawbacks of classical free electron theory.
28. State quantum theory of free electron.
29. Mention the important features of quantum free electron theory of metals.
30. What are the important applications of quantum free electron theory?
31. Aluminium has three valence electrons and copper has one valence electron. Why do we have large
electrical conductivity for copper than Aluminium?
32. What are the differences between quantum theory and zone theory?
33. Write Fermi-Dirac distribution function and give its importance.
34. Write down the expression for the Fermi Dirac distribution law and explain it for the electrons in a metal.
35. Draw the Fermi energy distribution curve at 0 K and at any temperature ‘T’K.
36. Define Fermi energy level and Fermi energy with their importance.
37. Define Fermi energy surface (or) Fermi sphere and give its importance.
38. Why is that only the electrons near the Fermi level contribute to electrical conductivity?
39. Define density of states with example. States its importance.
PART - B
40. What is meant by Fermi energy of a metal?
1. Explain classical free electron theory of metals. Give its merits and drawbacks.
2. On the basis of free electron theory. Derive an expression for the electrical and thermal conductivities of
metal and hence establish Wiedemann-Franz Law.
3. State and prove Wiedemann-Franz Law.
4. Discuss classical free electron theory of metals. Obtain the expression for electrical resistivity in terms of
about:blank 1/11
, 10/10/23, 9:18 AM Engineering physics
35. Draw the Fermi energy distribution curve at 0 K and at any temperature T K.
36. Define Fermi energy level and Fermi energy with their importance.
37. Define Fermi energy surface (or) Fermi sphere and give its importance.
38. Why is that only the electrons near the Fermi level contribute to electrical conductivity?
39. Define density of states with example. States its importance.
PART - B
40. What is meant by Fermi energy of a metal?
1. Explain classical free electron theory of metals. Give its merits and drawbacks.
2. On the basis of free electron theory. Derive an expression for the electrical and thermal conductivities of
metal and hence establish Wiedemann-Franz Law.
3. State and prove Wiedemann-Franz Law.
4. Discuss classical free electron theory of metals. Obtain the expression for electrical resistivity in terms of
well known microscope quantities. Discuss the dependence on temperature.
5. (a) What are the postulates of classical free electron theory?
(b) Derive an expression connecting electrical conductivity and relaxation time.
6. a) Deduce an expression for electrical conductivity of conducting material
b) List out the drawbacks of classical free electrons theory
7. Deduce a mathematical expression for electrical conductivity and thermal conductivity of a conducting
material and hence obtain Wiedemann-Franz Law.
8. Write Fermi-Dirac distribution function. Explain how Fermi function varies with temperature?
9. Write down the Fermi-Dirac equation for the probability of occupation of an energy level E by an electron.
Show that the probability of its occupancy by an electron is zero if E > EF and unity if E < E F at temperature
0K
10. Define density of energy states. Derive an expression for the density of energy states and carrier
concentration in a metal by using the Fermi distribution function.
11. i) Obtain an expression for the density of states for a metal.
ii) State the merits and demerits of classical free electron theory.
12. What is density of states? Derive an expression for density of states and using that obtain an expression for
Fermi energy of a metal of O K.
13. i) Define Fermi energy.
ii) Explain Fermi Dirac distribution for electrons in a metal.
iii) Obtain an expression for Fermi energy at temperature T=O and relate it to Fermi energy at non zero
temperature.
14. i) Explain the meaning of ‘density of states’. Derive an expression for the number of allowed states for unit
volume of a solid.
ii) Write an expression for the Fermi energy distribution function FD (E) and discuss its behavior with
change in temperature. Plot FD (E) versus E for T=0K, and T>0K.
15. Derive an expression for carrier concentration in a metal by using the Fermi distribution function. Explain
the variation of Fermi level with temperature.
16. i) Define Fermi energy.
ii) Explain Fermi Dirac distribution for electrons in a metal.
iii) Obtain an expression for Fermi energy at temperature = 0 K and relate it to Fermi energy at non zero
temperature.
17. Write a short notes on classical theory, Fermi – Dirac distribution, wideemann – franz law
18. Explain the dependence of electrical conductivity on temperature on impurities.
Unit – II – SEMICONDUCTING MATERIALS
PART – A
1. What are semiconductors? Give example.
2. State the properties of semiconductor.
4. 3.
What are theany
Mention types of advantages
four semiconductor?
of semiconducting materials.
5. What are intrinsic and extrinsic semiconductors? Give examples.
6. Mention the applications of extrinsic semiconductors.
7. Distinguish intrinsic and extrinsic semiconductor?
8. What is meant by doping and doping level?
9. How are n-type and p-type semi conductors produced?
10. You are given a piece of extrinsic semiconductor. How will you find to which type it belongs?
11 What is the effect of impurity states over extrinsic semiconductors?
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