ECAT Pre General Science Chapter 18 online mcq test with answers for Physics chapter 18 (Electronics)

Question # 1

All the valence electrons present in a crystal of silicon are bound in their orbits by

Ionic bond A
covalent bond B
Molecular bond C
Both (A) and (B) D
Both (B) and (C) E

Question # 2

In an N-type silicon, which of the following statement is true

Electrons are majority carriers and trivalent atoms are the dopants A
Electrons are minority carriers and pentavalent atoms are the dopants B
Holes are minority carriers and pentavalent atoms are the dopants C
Holes are majority carriers and trivalent atoms are the dopants D

Question # 3

Most of the electrons in the base of an NPN transistor flow

Out of the base lead A
Into the collector B
Into the emit C
Into the base supply D

Question # 4

Depletion region contains:

Protons A
Positive ions B
Negative ions C
Both (B) and (C) D
Both (A) and (C) E

Question # 5

The SI unit of charge is

Ampere A
Watt B
Coulomb C
Volt D
Joule E

Question # 6

If both the inputs given to a gate ae 1 such that the output is 0, then it is:

AND gate A
NOR gate B
OR gate C
NOT gate D
Both (A) and (C) E

Question # 7

When transistors are used in digital circuits they usually operate in the

Active region A
Breakdown region B
Saturation and cutoff regions C
Linear region D

Question # 8

The concept of electric field theory was introduced by

Michael Faraday A
Newton B
Dalton C
Kepler D
Einstein E

Question # 9

In reverse-biased p-n junction, the reverse current is due to flow of:

Minority charge carriers A
Majority charge carriers B
Free electrons from p to n-region C
Holes from n to p-region D
all are true except (B) E

Question # 10

In AND gate, the output is 1 if:

Both inputs are 0 A
Both inputs are 1 B
Only one input is 0 C
Both (A) and (B) D
Both (A) and (C) E

Question # 11

A potential barrier of 0.7V exists across p-n junction made from:

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 12

Majority charge carriers in the p-region of p-n junction are:

electrons A
positrons B
Holes C
Neutrons D
None of these E

Question # 13

Michael Faraday is known by his work on

Nuclear strong force A
Gravitational force B
Nuclear weak force C
Electric force D
None of these E

Question # 14

In full wave rectification, simultaneous action is that:

Two diodes conduct and two do not. A
One diode conduct and three do not. B
Three diodes conduct and one does not. C
All the four diodes conduct D
None of these E

Question # 15

Origin of the electric and the gravitational forces

Was known in 1911 A.D. A
Was known in 1811 A.D. B
Was known in 1711 A.D. C
is still unknown D
Was known in 1611 A.D. E

Question # 16

A diode which can turn its current ON and OFF in nono seconds is called:

LED A
Photodiode B
An ordinary diode. C
Both (A) and (B) D
Both (B) and (C) E

Question # 17

A hole in p-type my be due to:

Trivalent impurity A
Breking of some covalent bond B
Pentavalent impurity C
Germanium D
Either (A) or (B) E

Question # 18

Truth table of logic function:

Summarizes its output values A
Tabulates all its input conditions only B
Display all its input/output possibilites C
Is not based on logic algebra D
None of these E

Question # 19

In describing function of digital systems, 1 represents:

Closed switch A
True Statement B
Lighted bulb C
Only (B) and (C) D
All are true E

Question # 20

To designate the voltage as low or 0 by a logic gate, the specified minimum value is:

0.2 volt A
0.8 volt B
0 volt C
2.0 volt D
5.0 volt E

Question # 21

Silicon is one of the mot commonly used:

onductor A
Dielectric B
Insulator C
Semiconduction D
Both (B) and (C) E

Question # 22

The use of chips in electrons is described in the form of:

Yellow boxes A
Black boxes B
Red boxes C
White boxes D
Orange boxes E

Question # 23

The value of LDR depends upon intensity of:

Sound falling on it A
Current passing through it B
Magnetic field surrounding it C
Light falling on it D
Non of these E

Question # 24

The reverse saturation current in a PN junction diode is only due to

Majority carriers A
Minority Carriers B
Acceptor ions C
Donor ions D

Question # 25

A transistor has:

One region A
Two regions B
Three regions C
Four regions D
None is correct E

Question # 26

An LED emits light when it is:

Forward biased A
Reverse biased B
Operated without battery C
Operated with heat source D
None of these E

Question # 27

By placing a dielectric in between the charges, the electrostatic force between them

Is always reduced A
Is always increased B
Is not affected C
Is increased one million times D
None of these E

Question # 28

Electric field lines emerge from the charges in

One dimension A
Two dimensions B
Three dimensions C
Four dimensions D
None of these E

Question # 29

The intensity at a point due to a charge is inversely proportional to

Amount of charge A
Size of the charge B
Distance between charge and the point C
Square of the distance from the charge D
None of these E

Question # 30

Inverter is the name given to:

NOT gate A
OR gate B
NOR gate C
AND gate D
XOR gate E

Sr.#	Question	Answer
1	Computer chips are made from:	A. Iron B. Silicon C. Helium D. Stontium
2	The electric field lines start from	A. Positive charge B. Negative charge C. Either A or B D. Neutron
3	When transistors are used in digital circuits they usually operate in the	A. Active region B. Breakdown region C. Saturation and cutoff regions D. Linear region
4	Inverter is the name given to:	A. NOT gate B. OR gate C. NOR gate D. AND gate
5	To make an LED, it is impreacticable to use:	A. Silicon B. Gallium arsenide C. Gallium arsenide phosphide D. Iron
6	The reverse saturation current in a PN junction diode is only due to	A. Majority carriers B. Minority Carriers C. Acceptor ions D. Donor ions
7	Whenever a covalent bond breaks, it creates:	A. An electron B. A hole C. An electron-hole pair D. A positron
8	If both the inputs given to a gate ae 1 such that the output is 0, then it is:	A. AND gate B. NOR gate C. OR gate D. NOT gate
9	A diode which can turn its current ON and OFF in nono seconds is called:	A. LED B. Photodiode C. An ordinary diode. D. Both (A) and (B)
10	The value of LDR depends upon intensity of:	A. Sound falling on it B. Current passing through it C. Magnetic field surrounding it D. Light falling on it

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ECAT Pre General Science Physics Chapter 18 MCQ Test With Answer

MCQ's Test For ECAT Pre General Science Physics Chapter 18 Electronics

ECAT Pre General Science Physics Chapter 18 Electronics