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

Question # 1

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 # 2

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

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

Question # 3

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 # 4

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 # 5

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 # 6

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 # 7

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 # 8

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 # 9

The electric field lines start from

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

Question # 10

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 # 11

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 # 12

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 # 13

A transistor has:

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

Question # 14

Depletion region contains:

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

Question # 15

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 # 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

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 # 18

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 # 19

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 # 20

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 # 21

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 # 22

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 # 23

An electronic computer is basically a vast arrangement of electronic switches which are made from

Resistors A
Transistors B
N -type crystals C
P-Type crystals D
Capacitors E

Question # 24

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 # 25

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 # 26

Improper biasing of a transistor circuit produces

Heavy loading of emitter current A
Distortion in the output signal B
Excessive heat at collector terminal C
Faulty location of load line D

Question # 27

Inverter is the name given to:

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

Question # 28

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 # 29

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 # 30

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

Four A
Five B
Nine C
Six D
Seven 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	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)
3	.Depletion region contains:	A. Protons B. Positive ions C. Negative ions D. Both (B) and (C)
4	The electric field lines start from	A. Positive charge B. Negative charge C. Either A or B D. Neutron
5	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
6	The SI unit of charge is	A. Ampere B. Watt C. Coulomb D. Volt
7	All the valence electrons present in a crystal of silicon are bound in their orbits by	A. Ionic bond B. covalent bond C. Molecular bond 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	A digital system deals with quantities which has discrete values:	A. Two in number B. One in number C. Three in number D. Four in number
10	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

Latest Educational News Stories

Pakistan's Largest Database of Colleges and Universities

BS Programs

University Past Papers

University Results

Exam Results 2024

Study Abroad Programs and Opportunities for Pakistani Students

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