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

Question # 1

If the distance between two charges is doubled, the force between them will become

Double A
Half B
Three times C
One fourth D
One third E

Question # 2

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 # 3

In the text book, the transistor amplifier circuit is a:

Common emitter circuit A
Common collector circuit B
Common base circuit C
Any of these D
None of these E

Question # 4

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

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 5

To make an LED, it is impreacticable to use:

Silicon A
Gallium arsenide B
Gallium arsenide phosphide C
Iron D
Both (B) and (C) E

Question # 6

The SI unit of charge is

Ampere A
Watt B
Coulomb C
Volt D
Joule E

Question # 7

A digital system deals with quantities which has discrete values:

Two in number A
One in number B
Three in number C
Four in number D
None of these E

Question # 8

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 # 9

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 # 10

.Depletion region contains:

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

Question # 11

Whenever a covalent bond breaks, it creates:

An electron A
A hole B
An electron-hole pair C
A positron D
All of these E

Question # 12

The values 1 and 0 are designated as:

Continuous values A
Binary values B
Boolean values C
Decimal values D
Either (B) and (C) E

Question # 13

To display a digit of EIGHT, the number of ON LED'S are:

Two A
Three B
Five C
Seven D
Eight E

Question # 14

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 # 15

Electric field strength is defined as

Work done on unit charge A
Force exerted on unit charge B
Distance covered by unit charge C
Power exerted by unit charge D
None of these E

Question # 16

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 # 17

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 # 18

In a transistor, collector current is controlled by

Collector voltage A
Base current B
Collector resistance C
All of the above D

Question # 19

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 # 20

The electric field lines start from

Positive charge A
Negative charge B
Either A or B C
Neutron D
An atom E

Question # 21

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 # 22

The value of relative permittivity of different dielectrics are

Equal A
Different B
Greater than one C
Smaller than one D
Both B and C E

Question # 23

Crystal of germanium or silicon in its pure form at absolute zero acts as:

A conductor A
A semiconductor B
an insulator C
Both (A) and (C) D
Both (A) and (B) E

Question # 24

Inverter is the name given to:

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

Question # 25

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 # 26

Electric lines of force

Intersect each other A
Are always parallel B
Are always anti-parallel C
Never intersect D
None of these E

Question # 27

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 # 28

Silicon is one of the mot commonly used:

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

Question # 29

A transistor has:

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

Question # 30

Depletion region contains:

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

Sr.#	Question	Answer
1	In AND gate, the output is 1 if:	A. Both inputs are 0 B. Both inputs are 1 C. Only one input is 0 D. Both (A) and (B)
2	Crystal of germanium or silicon in its pure form at absolute zero acts as:	A. A conductor B. A semiconductor C. an insulator D. Both (A) and (C)
3	The number of LED'S needed to display all the digits is:	A. Four B. Five C. Nine D. Six
4	Inverter is the name given to:	A. NOT gate B. OR gate C. NOR gate D. AND gate
5	Op-amp has been discussed as comparator of:	A. Distances B. Voltages C. Velocities D. Magnetic fields
6	A potential barrier of 0.7 V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
7	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)
8	Most of the electrons in the base of an NPN transistor flow	A. Out of the base lead B. Into the collector C. Into the emit D. Into the base supply
9	To display a digit of EIGHT, the number of ON LED'S are:	A. Two B. Three C. Five D. Seven
10	Improper biasing of a transistor circuit produces	A. Heavy loading of emitter current B. Distortion in the output signal C. Excessive heat at collector terminal D. Faulty location of load line

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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