# Basic Physics 4

First Year Engineering Common to all Branches: Basic Physics 4

Subject: Basic Physics 4

Part 4: List for questions and answers of Basic Physics

Q1. Energy band formation is prominent in
a) soilds
b) liquids
c) gases
d) all the above

Q2. Compared to vacuum devices, the advantages of semiconductor devices is that they…..
a) operate at low voltage
b) have low power consumption
c) occupy less space
d) all the above

Q3. ……… band contains free electrons
a) Valance
b) Conduction
c) Forbidden
d) both conduction and valance band

Q4. If N atoms are brought close together to form a solid, the p energy band can
accommodate …….. electrons.
a) N
b) 2N
c) 6 N
d) 8 N

Q5. If the outermost energy band in a solid is completely filled, the solid will be ……..
a) insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q6. If the outermost energy band in solids is completely filled and energy difference with next empty energy band is small, the solid will be …….
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q7. If the outermost energy band in solids is completely filled and energy difference with next empty energy band is large, the solid will be …….
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q8. If the outermost energy band in a solid is partially filled, the solid will be ……..
a) insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q9. Conduction band of a semiconductor at temperature above 0 K will be ….
a) Completely filled
b) partially filled
c) insulators
d) both semiconductors and insulators

Q10. Near room temperature, resistivity is maximum for
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q11. Resistivity increases with increase in temperature for
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q12. Near room temperature resistivity is minimum for
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q13. If a semiconductor is transparent to light of wavelength than λ, the band gap energy will be
a) h λ/c
b) hc/ λ
c) h/ λ
d) λc/h

Q14. If band gap energy of a semiconductor is Eg, the material will be ………
a) transparent to wavelength greater than hc/Eg
b) opaque to wavelength greater than hc/Eg
c) transparent to wavelength less than hc/Eg
d) none of these

Q15. Which of the following have a positive temperature coefficient?
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q16. Which of the following have a negative temperature coefficient?
a) Insulator
b) semiconductor
c) good conductor
d) either insulator or good conductor

Q17. Pure semiconductor is known as
a) intrinsic
b) doped
c) extrinsic
d) compound

Q18. Which of the following is added to a pure semiconductor to get a n-type
semiconductor
a) Phosphorus
b) Aluminium
c) Gallium
d) Indium

Q19. The majority charge carriers in p-type semiconductor are
a) free electrons
b) holes
c) both holes and free electrons
d) neither free electrons nor holes

Q20. The majority charge carriers in n-type semiconductor are
a) free electrons
b) holes
c) both holes and free electrons
d) neither free electrons nor holes

Part 4: List for questions and answers of Basic Physics