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

Question # 1

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 # 2

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 # 3

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 # 4

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 # 5

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 # 6

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 # 7

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 # 8

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

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

Question # 9

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 # 10

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

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 11

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 # 12

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 # 13

Silicon is one of the mot commonly used:

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

Question # 14

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 # 15

A transistor has:

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

Question # 16

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

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

Question # 17

In a transistor, collector current is controlled by

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

Question # 18

The electric field lines start from

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

Question # 19

The concept of electric field theory was introduced by

Michael Faraday A
Newton B
Dalton C
Kepler D
Einstein E

Question # 20

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 # 21

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 # 22

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 # 23

Op-amp has been discussed as comparator of:

Distances A
Voltages B
Velocities C
Magnetic fields D
Both (A) and (C) 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 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 # 26

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 # 27

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 # 28

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 # 29

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 # 30

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

Sr.#	Question	Answer
1	To make an LED, it is impreacticable to use:	A. Silicon B. Gallium arsenide C. Gallium arsenide phosphide D. Iron
2	A hole in p-type my be due to:	A. Trivalent impurity B. Breking of some covalent bond C. Pentavalent impurity D. Germanium
3	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
4	Electric lines of force	A. Intersect each other B. Are always parallel C. Are always anti-parallel D. Never intersect
5	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)
6	In a transistor, collector current is controlled by	A. Collector voltage B. Base current C. Collector resistance D. All of the above
7	In reverse-biased p-n junction, the reverse current is due to flow of:	A. Minority charge carriers B. Majority charge carriers C. Free electrons from p to n-region D. Holes from n to p-region
8	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
9	A transistor has:	A. One region B. Two regions C. Three regions D. Four regions
10	To turn the transistor OFF, the base current is set:	A. At maximum value B. At zero C. Either (A) or (B) D. All are correct

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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