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

Question # 1

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 # 2

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

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

Question # 3

Op-amp has been discussed as comparator of:

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

Question # 4

To display a digit of EIGHT, the number of ON LED'S are:

Two A
Three B
Five C
Seven D
Eight E

Question # 5

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 # 6

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 # 7

The concept of electric field theory was introduced by

Michael Faraday A
Newton B
Dalton C
Kepler D
Einstein E

Question # 8

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 # 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

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 # 11

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 # 12

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 # 13

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 # 14

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 # 15

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 # 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

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 # 19

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 # 20

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 # 21

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 # 22

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 # 23

Field lines are closer to each other in the region where the filed is

Stronger A
Weaker B
Much weaker C
Absent D
None of these E

Question # 24

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 # 25

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 # 26

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 # 27

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 # 28

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 # 29

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 # 30

Electric lines of force

Intersect each other A
Are always parallel B
Are always anti-parallel C
Never intersect D
None of these E

Sr.#	Question	Answer
1	An LED emits light when it is:	A. Forward biased B. Reverse biased C. Operated without battery D. Operated with heat source
2	Electric intensity at a place due to a charged conductor is a	A. Scalar quantity B. Vector quantity C. Semi vector and semi scalar D. Dimensionless quantity
3	When transistors are used in digital circuits they usually operate in the	A. Active region B. Breakdown region C. Saturation and cutoff regions D. Linear region
4	The use of chips in electrons is described in the form of:	A. Yellow boxes B. Black boxes C. Red boxes D. White boxes
5	The number of LED'S needed to display all the digits is:	A. Four B. Five C. Nine D. Six
6	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)
7	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
8	A potential barrier of 0.7 V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
9	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
10	Michael Faraday is known by his work on	A. Nuclear strong force B. Gravitational force C. Nuclear weak force D. Electric force

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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