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

Question # 1

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 # 2

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 # 3

A transistor has:

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

Question # 4

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

Four A
Five B
Nine C
Six D
Seven E

Question # 5

The SI unit of charge is

Ampere A
Watt B
Coulomb C
Volt D
Joule E

Question # 6

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 # 7

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

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

Question # 8

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 # 9

.Depletion region contains:

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

Question # 10

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 # 11

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 # 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

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 # 14

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 # 15

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 # 16

In a transistor, collector current is controlled by

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

Question # 17

Computer chips are made from:

Iron A
Silicon B
Helium C
Stontium D
Aluminium E

Question # 18

The concept of electric field theory was introduced by

Michael Faraday A
Newton B
Dalton C
Kepler D
Einstein E

Question # 19

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 # 20

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 # 21

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 # 22

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 # 23

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 # 24

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 # 25

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 # 26

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 # 27

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 # 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

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 # 30

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

Sr.#	Question	Answer
1	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
2	The number of input terminals of an op-amp is:	A. One B. Two C. Three D. Four
3	Inverter is the name given to:	A. NOT gate B. OR gate C. NOR gate D. AND gate
4	Silicon is one of the mot commonly used:	A. onductor B. Dielectric C. Insulator D. Semiconduction
5	Truth table of logic function:	A. Summarizes its output values B. Tabulates all its input conditions only C. Display all its input/output possibilites D. Is not based on logic algebra
6	In describing function of digital systems, 1 represents:	A. Closed switch B. True Statement C. Lighted bulb D. Only (B) and (C)
7	The electric field lines start from	A. Positive charge B. Negative charge C. Either A or B D. Neutron
8	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)
9	A potential barrier of 0.7V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
10	All the valence electrons present in a crystal of silicon are bound in their orbits by	A. Ionic bond B. covalent bond C. Molecular bond D. Both (A) and (B)
11	In a transistor, collector current is controlled by	A. Collector voltage B. Base current C. Collector resistance D. All of the above
12	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
13	Most of the electrons in the base of an NPN transistor flow	A. Out of the base lead B. Into the collector C. Into the emit D. Into the base supply
14	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
15	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
16	.Depletion region contains:	A. Protons B. Positive ions C. Negative ions D. Both (B) and (C)
17	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
18	In the text book, the transistor amplifier circuit is a:	A. Common emitter circuit B. Common collector circuit C. Common base circuit D. Any of these
19	An LED emits light when it is:	A. Forward biased B. Reverse biased C. Operated without battery D. Operated with heat source
20	Field lines are closer to each other in the region where the filed is	A. Stronger B. Weaker C. Much weaker D. Absent
21	Whenever a covalent bond breaks, it creates:	A. An electron B. A hole C. An electron-hole pair D. A positron
22	To display a digit of EIGHT, the number of ON LED'S are:	A. Two B. Three C. Five D. Seven
23	Electric field strength is defined as	A. Work done on unit charge B. Force exerted on unit charge C. Distance covered by unit charge D. Power exerted by unit charge
24	A potential barrier of 0.7 V exists across p-n junction made from:	A. Germanium B. Silicon C. Arsenic D. Gallium
25	A hole in p-type my be due to:	A. Trivalent impurity B. Breking of some covalent bond C. Pentavalent impurity D. Germanium
26	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

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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