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

Question # 1

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

Four A
Five B
Nine C
Six D
Seven 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

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 # 4

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 # 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

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 # 7

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 # 8

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 # 9

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 # 10

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 # 11

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 # 12

Silicon is one of the mot commonly used:

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

Question # 13

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 # 14

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

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

Question # 15

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 # 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

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 # 18

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 # 19

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 # 20

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

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

Question # 21

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 # 22

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 # 23

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 # 24

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 # 25

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 # 26

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 # 27

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

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 28

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 # 29

Depletion region contains:

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

Question # 30

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

Sr.#	Question	Answer
1	The value of LDR depends upon intensity of:	A. Sound falling on it B. Current passing through it C. Magnetic field surrounding it D. Light falling on it
2	In describing function of digital systems, 1 represents:	A. Closed switch B. True Statement C. Lighted bulb D. Only (B) and (C)
3	Field lines are closer to each other in the region where the filed is	A. Stronger B. Weaker C. Much weaker D. Absent
4	The number of input terminals of an op-amp is:	A. One B. Two C. Three D. Four
5	In a transistor, collector current is controlled by	A. Collector voltage B. Base current C. Collector resistance D. All of the above
6	Electric field lines emerge from the charges in	A. One dimension B. Two dimensions C. Three dimensions D. Four dimensions
7	The values 1 and 0 are designated as:	A. Continuous values B. Binary values C. Boolean values D. Decimal values
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	Inverter is the name given to:	A. NOT gate B. OR gate C. NOR gate D. AND gate
10	Computer chips are made from:	A. Iron B. Silicon C. Helium D. Stontium

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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