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

Question # 1

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 # 2

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 # 3

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 # 4

.Depletion region contains:

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

Question # 5

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 # 6

The electric field lines start from

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

Question # 7

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 # 8

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 # 9

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 # 10

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 # 11

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 # 12

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 # 13

Inverter is the name given to:

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

Question # 14

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 # 15

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 # 16

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 # 17

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 # 18

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

Four A
Five B
Nine C
Six D
Seven E

Question # 19

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

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 20

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 # 21

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 # 22

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 # 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

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 # 25

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 # 26

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 # 27

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 # 28

Computer chips are made from:

Iron A
Silicon B
Helium C
Stontium D
Aluminium E

Question # 29

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 # 30

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

Sr.#	Question	Answer
1	An electronic computer is basically a vast arrangement of electronic switches which are made from	A. Resistors B. Transistors C. N -type crystals D. P-Type crystals
2	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)
3	Silicon is one of the mot commonly used:	A. onductor B. Dielectric C. Insulator D. Semiconduction
4	To make an LED, it is impreacticable to use:	A. Silicon B. Gallium arsenide C. Gallium arsenide phosphide D. Iron
5	Whenever a covalent bond breaks, it creates:	A. An electron B. A hole C. An electron-hole pair D. A positron
6	The use of chips in electrons is described in the form of:	A. Yellow boxes B. Black boxes C. Red boxes D. White boxes
7	.Depletion region contains:	A. Protons B. Positive ions C. Negative ions D. Both (B) and (C)
8	In full wave rectification, simultaneous action is that:	A. Two diodes conduct and two do not. B. One diode conduct and three do not. C. Three diodes conduct and one does not. D. All the four diodes conduct
9	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
10	A hole in p-type my be due to:	A. Trivalent impurity B. Breking of some covalent bond C. Pentavalent impurity D. Germanium

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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