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

Question # 1

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 # 2

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 # 3

A transistor has:

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

Question # 4

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 # 5

Inverter is the name given to:

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

Question # 6

Computer chips are made from:

Iron A
Silicon B
Helium C
Stontium D
Aluminium E

Question # 7

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 # 8

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 # 9

The concept of electric field theory was introduced by

Michael Faraday A
Newton B
Dalton C
Kepler D
Einstein E

Question # 10

The SI unit of charge is

Ampere A
Watt B
Coulomb C
Volt D
Joule E

Question # 11

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 # 12

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 # 13

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 # 14

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 # 15

.Depletion region contains:

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

Question # 16

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 # 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

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 # 19

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 # 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

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 # 22

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 # 23

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 # 24

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 # 25

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 # 26

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 # 27

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 # 28

Op-amp has been discussed as comparator of:

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

The number of input terminals of an op-amp is:

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

Sr.#	Question	Answer
1	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
2	An LED emits light when it is:	A. Forward biased B. Reverse biased C. Operated without battery D. Operated with heat source
3	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
4	Whenever a covalent bond breaks, it creates:	A. An electron B. A hole C. An electron-hole pair D. A positron
5	To designate the voltage as low or 0 by a logic gate, the specified minimum value is:	A. 0.2 volt B. 0.8 volt C. 0 volt D. 2.0 volt
6	In an N-type silicon, which of the following statement is true	A. Electrons are majority carriers and trivalent atoms are the dopants B. Electrons are minority carriers and pentavalent atoms are the dopants C. Holes are minority carriers and pentavalent atoms are the dopants D. Holes are majority carriers and trivalent atoms are the dopants
7	A potential barrier of 0.7V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
8	Depletion region contains:	A. Protons B. Positive ions C. Negative ions D. Both (B) and (C)
9	In the forward biases situation, the current flowing across the p-n junction is a few:	A. amperes B. Milli amperes C. Micro amperes D. Pico amperes
10	In describing function of digital systems, 1 represents:	A. Closed switch B. True Statement C. Lighted bulb D. Only (B) and (C)

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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