In This Post we are providing Chapter-14 Semiconductor Electronic : Material, Devices and Simple Circuits NCERT MCQ for Class 12 Physics which will be beneficial for students. These solutions are updated according to 2021-22 syllabus. These MCQS can be really helpful in the preparation of Board exams and will provide you with a brief knowledge of the chapter.
NCERT MCQ ON SEMICONDUCTOR ELECTRONIC: MATERIAL, DEVICES AND SIMPLE CIRCUITS
Q.1. In a semiconductor
(a) there are no free electrons at 0 K
(b) there are no free electrons at any temperature
(c) the number of free electrons increases with pressure
(d) the number of free electrons is more than that in a conductor.
Answer: (a)
Q.2. Let nh and ne be the number of holes and conduction electrons in an extrinsic semiconductor. Then
(a) nh > ne
(b) nh = ne
(c) nh < ne
(d) nh ≠ ne
Answer: (d)
Q.3. A p-type semiconductor is
(a) positively charged
(b) negatively charged
(c) uncharged
(d) uncharged at 0K but charged at higher temperatures
Answer: (c)
Q.4. Electric conduction in a semiconductor takes place due to
(a) electrons only
(b) holes only
(c) both electrons and holes
(d) neither electrons nor holes
Answer: (c)
Q.5. The impurity atoms with which pure silicon may be doped to make it a p-type semiconductor are those of
(a) phosphorus
(b) boron
(c) antimony
(d) nitrogen
Answer: (b)
Q.6. The electrical conductivity of pure germanium can be increased by
(a) increasing the temperature
(b) doping acceptor impurities
(c) doping donor impurities
(d) All of the above
Answer: (d)
Q.7. The resistivity of a semiconductor at room temperature is in between
(a) 10–2 to 10–5 Ω cm
(b) 10–3 to 106 Ω cm
(c) 106 to 108 Ω cm
(d) 1010 to 1012 Ω cm
Answer: (b)
Q.8. Number of electrons in the valence shell of a pure semiconductor is
(a) 1
(b) 2
(c) 3
(d) 4
Answer: (d)
Q.9. In a semiconductor, the forbidden energy gap between the valence band and the conduction band is of the order is
(a) 1 MeV
(b) 0.1 MeV
(c) 1 eV
(d) 5 eV
Answer: (c)
Q.10. The forbidden energy gap for germanium crystal at 0 K is
(a) 0.071 eV
(b) 0.71 eV
(c) 2.57 eV
(d) 6.57 eV
Answer: (b)
Q.11. In an insulator, the forbidden energy gap between the valence band and conduction band is of the order of
(a) 1 MeV
(b) 0.1 MeV
(c) 1 eV
(d) 5 eV
Answer: (d)
Q.12. What is the resistivity of a pure semiconductor at absolute zero ?
(a) Zero
(b) Infinity
(c) Same as that of conductors at room temperature
(d) Same as that of insulators at room temperature
Answer: (b)
Q.13. Temperature coefficient of resistance of semiconductor is
(a) zero
(b) constant
(c) positive
(d) negative
Answer: (d)
Q.14. In a p-type semiconductor, the acceptor valence band is
(a) close to the valence band of the host crystal
(b) close to conduction band of the host crystal
(c) below the conduction band of the host crystal
(d) above the conduction band of the host crystal
Answer: (a)
Q.15. In an n-type semiconductor, donor valence band is
(a) above the conduction band of the host crystal
(b) close to the valence band of the host crystal
(c) close to the conduction band of the host crystal
(d) below the valence band of the host crystal
Answer: (c)
Discover more from EduGrown School
Subscribe to get the latest posts sent to your email.