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

Question # 1

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 # 2

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 # 3

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 # 4

To turn the transistor OFF, the base current is set:

At maximum value A
At zero B
Either (A) or (B) C
All are correct D
None of correct E

Question # 5

In a transistor, collector current is controlled by

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

Question # 6

Conversion of A.C. into D.C. is called:

Reftification A
Amplification B
Electric induction C
Magnetic induction D
None of these E

Question # 7

Electric intensity at a place due to a charged conductor is a

Scalar quantity A
Vector quantity B
Semi vector and semi scalar C
Dimensionless quantity D
Both A and D are true E

Question # 8

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 # 9

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 # 10

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 # 11

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 # 12

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 # 13

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 # 14

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 # 15

.Depletion region contains:

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

Question # 16

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 # 17

Depletion region contains:

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

Question # 18

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 # 19

Op-amp has been discussed as comparator of:

Distances A
Voltages B
Velocities C
Magnetic fields D
Both (A) and (C) E

Question # 20

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 # 21

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 # 22

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 # 23

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 # 24

The electric field lines start from

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

Question # 25

Inverter is the name given to:

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

Question # 26

A transistor has:

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

Question # 27

In the forward biases situation, the current flowing across the p-n junction is a few:

amperes A
Milli amperes B
Micro amperes C
Pico amperes D
None of these E

Question # 28

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 # 29

The number of LED'S needed to display all the digits is:

Four A
Five B
Nine C
Six D
Seven E

Question # 30

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

Sr.#	Question	Answer
1	A potential barrier of 0.7V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
2	Truth table of logic function:	A. Summarizes its output values B. Tabulates all its input conditions only C. Display all its input/output possibilites D. Is not based on logic algebra
3	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)
4	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
5	Origin of the electric and the gravitational forces	A. Was known in 1911 A.D. B. Was known in 1811 A.D. C. Was known in 1711 A.D. D. is still unknown
6	The value of relative permittivity of different dielectrics are	A. Equal B. Different C. Greater than one D. Smaller than one
7	The intensity at a point due to a charge is inversely proportional to	A. Amount of charge B. Size of the charge C. Distance between charge and the point D. Square of the distance from the charge
8	The values 1 and 0 are designated as:	A. Continuous values B. Binary values C. Boolean values D. Decimal values
9	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)
10	By placing a dielectric in between the charges, the electrostatic force between them	A. Is always reduced B. Is always increased C. Is not affected D. Is increased one million times

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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