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

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 # 3

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 # 4

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 # 5

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 # 6

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

Four A
Five B
Nine C
Six D
Seven E

Question # 7

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

Germanium A
Silicon B
Arsenic C
Gallium D
Indium E

Question # 8

The SI unit of charge is

Ampere A
Watt B
Coulomb C
Volt D
Joule E

Question # 9

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 # 10

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 # 11

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 # 12

Depletion region contains:

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

Question # 13

An electronic computer is basically a vast arrangement of electronic switches which are made from

Resistors A
Transistors B
N -type crystals C
P-Type crystals D
Capacitors E

Question # 14

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 # 15

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 # 16

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 # 17

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 # 18

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 # 19

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 # 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

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 # 22

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

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

Question # 23

Computer chips are made from:

Iron A
Silicon B
Helium C
Stontium D
Aluminium E

Question # 24

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 # 25

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 # 26

Inverter is the name given to:

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

Question # 27

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 # 28

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 # 29

.Depletion region contains:

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

Question # 30

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

Sr.#	Question	Answer
1	The electric field lines start from	A. Positive charge B. Negative charge C. Either A or B D. Neutron
2	Electric lines of force	A. Intersect each other B. Are always parallel C. Are always anti-parallel D. Never intersect
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 field lines emerge from the charges in	A. One dimension B. Two dimensions C. Three dimensions D. Four dimensions
5	A transistor has:	A. One region B. Two regions C. Three regions D. Four regions
6	To make an LED, it is impreacticable to use:	A. Silicon B. Gallium arsenide C. Gallium arsenide phosphide D. Iron
7	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
8	The intensity at a point due to a charge is inversely proportional to	A. Amount of charge B. Size of the charge C. Distance between charge and the point D. Square of the distance from the charge
9	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
10	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
11	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
12	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
13	An electronic computer is basically a vast arrangement of electronic switches which are made from	A. Resistors B. Transistors C. N -type crystals D. P-Type crystals
14	Field lines are closer to each other in the region where the filed is	A. Stronger B. Weaker C. Much weaker D. Absent
15	Depletion region contains:	A. Protons B. Positive ions C. Negative ions D. Both (B) and (C)
16	The use of chips in electrons is described in the form of:	A. Yellow boxes B. Black boxes C. Red boxes D. White boxes
17	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
18	Silicon is one of the mot commonly used:	A. onductor B. Dielectric C. Insulator D. Semiconduction
19	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)
20	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
21	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
22	The SI unit of charge is	A. Ampere B. Watt C. Coulomb D. Volt
23	Computer chips are made from:	A. Iron B. Silicon C. Helium D. Stontium
24	A hole in p-type my be due to:	A. Trivalent impurity B. Breking of some covalent bond C. Pentavalent impurity D. Germanium
25	Michael Faraday is known by his work on	A. Nuclear strong force B. Gravitational force C. Nuclear weak force D. Electric force
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