Check the below NCERT MCQ Questions for Class 12 Physics Chapter 14 Semiconductor Electronics: Materials, Devices and Simple Circuits with Answers Pdf free download. MCQ Questions for Class 12 Physics with Answers were prepared based on the latest exam pattern. We have provided Semiconductor Electronics: Materials, Devices and Simple Circuits Class 12 Physics MCQs Questions with Answers to help students understand the concept very well.
Semiconductor Electronics: Materials, Devices and Simple Circuits Class 12 MCQs Questions with Answers
Question 1.
Bonds in a semiconductor :
(a) trivalent
(b) covalent
(c) bivalent
(d) monovalent
Answer
Answer: (b) covalent
Question 2.
Number of electrons in the valence shell of a semiconductor is:
(a) 1
(b) 2
(c) 3
(d) 4
Answer
Answer: (d) 4
Question 3.
Semiconductors of both p-type and n-type are produced by:
(a) ionic solids
(b) covalent solids
(c) metallic solids
(d) molecular solids
Answer
Answer: (b) covalent solids
Question 4.
With fall of temperature, the forbidden energy gap of a semiconductor
(a) increases
(b) decreases
(c) sometimes increases and sometimes decreases
(d) remains unchanged
Answer
Answer: (d) remains unchanged
Question 5.
In a p-type semiconductor, current conduction is by:
(a) atoms
(b) holes
(c) electrons
(d) protons
Answer
Answer: (b) holes
Question 6.
The relation between number of free electrons (n) in a semiconductor and temperature (T) is given by:
(a) n ∝ T
(b) n ∝ T²
(c) n ∝ T1/2
(d) n ∝ T3/2
Answer
Answer: (d) n ∝ T3/2
Question 7.
In reverse biasing:
(a) large amount of current flows
(b) no current flows
(c) potential barrier across junction increases
(d) depletion layer resistance increases
Answer
Answer: (c) potential barrier across junction increases
Question 8.
Main function of a transistor is to :
(a) rectify
(b) simplify
(c) amplify
(d) all the above
Answer
Answer: (c) amplify
Question 9.
To obtain p-type silicon semiconductor, we need to dope pure silicon with:
(a) aluminium
(b) phosphorus
(c) oxygen
(d)germanium
Answer
Answer: (a) aluminium
Question 10.
On applying reverse bias to a junction diode, it:
(a) lowers the potential barrier
(b) raise the potential barrier
(c) increases the majority carrier current
(d) increases the minority carrier current
Answer
Answer: (b) raise the potential barrier
Question 11.
For germanium crystal, the forbidden energy gap in joules
(a) 1.216 × 10-19
(b) 1.76 × 10-19
(c) 1.6 × 10-19
(d) zero
Answer
Answer: (a) 1.216 × 10-19
Question 12.
To obtain electrons as majority charge carriers in a semiconductors the impurity mixed is:
(a) monovalent
(b) divalent
(c) trivalent
(d) pentavalent
Answer
Answer: (b) divalent
Question 13.
In the middle of the depletion layer of a reverse biased p-n junction, the:
(a) electric field is zero
(b) potential is maximum
(c) electric field is maximum
(d) potential zero.
Answer
Answer: (d) potential zero.
Question 14.
In a common base amplifier the phase difference between the input signal voltage and output voltage is :
(a) π/2
(b) 0
(c) π/4
(d) π
Answer
Answer: (b) 0
Question 15.
Energy bands in solids are a consequence of:
(a) Ohm’s Law
(b) Pauli’s exclusion principle
(c) Bohr’s theory
(d) Heisenberg’s uncertainty principle
Answer
Answer: (b) Pauli’s exclusion principle
Question 16.
In semi conductor which are responsible for conduction:
(a) only electron
(b) electron and hole both
(c) only hole
(d) None of these
Answer
Answer: (b) electron and hole both
Question 17.
In binary system III represents:
(a) 1
(b) 3
(c) 7
(d) 100
Answer
Answer: (c) 7
Question 18.
On heating, resistance of semiconductors:
(a) decreases
(b) increases
(c) remains same
(d) first increases then decreases
Answer
Answer: (a) decreases
Question 19.
p-n junction diode can be used as:
(a) amplifier
(b) oscillator
(c) detector
(d) modulator
Answer
Answer: (c) detector
Question 20.
In intrinsic semiconductor at room temperature, the number of electrons and holes are:
(a) equal
(b) unequal
(c) infinite
(d) zero
Answer
Answer: (a) equal
Question 21.
A forward biased diode is:
Answer
Answer: (a)
Question 22.
In full wave rectifier, input a.c. current has a frequency v. The output frequency of current is :
(a) V/2
(b) V
(c) 2V
(d) None
Answer
Answer: (c) 2V
Question 23.
Winch of the following gate is not an universal gate?
(a) OR
(b) NOT
(c) AND
(d) NAND
Answer
Answer: (d) NAND
Question 24.
Zener diode is used for:
(a) producing oscillations in a oscillator
(b) amplification
(c) stabilisation
(d) rectification
Answer
Answer: (c) stabilisation
Question 25.
In semi conductor, at room temperature :
(a) the valence bond is partially empty and the conduction band is partially filled
(b) the valence band is completely filled and the conduction band is partially filled
(c) the valence band is completely filled
(d) the conduction band is completely empty
Answer
Answer: (a) the valence bond is partially empty and the conduction band is partially filled
Question 26.
Crystal diode is:
(a) amplifying device
(b) fluctuating device
(c) non-linear device
(d) linear device
Answer
Answer: (c) non-linear device
Question 27.
The part of a transistor which is heavily doped to produce a large number of majority carriers is :
(a) base
(b) emitter
(c) collector
(d) None of these
Answer
Answer: (b) emitter
Question 28.
A p-type semiconductor is:
(a) negatively charged
(b) positively charged
(c) uncharged
(d) None of these
Answer
Answer: (c) uncharged
Question 29.
The material most commonly used to manufacture electronic solid state devices is :
(a) copper
(b) silicon
(c) germanium
(d) aluminium
Answer
Answer: (b) silicon
Question 30.
What is the number of possible crystal systems?
(a) 5
(b) 7
(c) 14
(d) 16
Answer
Answer: (b) 7
We hope the given NCERT MCQ Questions for Class 12 Physics Chapter 14 Semiconductor Electronics: Materials, Devices and Simple Circuits with Answers Pdf free download will help you. If you have any queries regarding Semiconductor Electronics: Materials, Devices and Simple Circuits CBSE Class 12 Physics MCQs Multiple Choice Questions with Answers, drop a comment below and we will get back to you soon.