ECAT Pre General Science Chapter 16 online mcq test with answers for Physics chapter 16 (Alternating Current)

Question # 1

When the pn-junction is in reversed biased, current flows through the junction due to the

majority carriers A
minority carriers B
either of them C
none of them D

Question # 2

For the normal operation of the transistor, its

emitter-base and collector base junctions are forward biased A
emitter-base junction is reversed biased and collector base junction is forward biased B
emitter-base junction is forward biased and collector-base junction is reverse biased C
any one of these D

Question # 3

Average value of A.C voltage during one cycle is

1 A
Zero B
Maximum C
Variable D

Question # 4

A digital system deals with quantities or variables which have

only one state A
only two discrete states B
three discrete states C
four discrete states D

Question # 5

The open loop gain of OP-AMP is of the order of

10² A
10³ B
10⁴ C
10⁵ D

Question # 6

The device which allows only the flow of an A.C. through a circuit is

Capacitor A
Inductor B
D.C. motor C
Battery D

Question # 7

A changing magnetic flux creates around itself

An electromotive force A
An electric field (changing electric flux) B
Magnetic field C
None of the above D

Question # 8

The entire wave form of sinusoidal voltage is actually a set of all the:

Positive maximum value + V_oand negative maximum value -V_o A
Posiotive maximum value +V_oand zero B
Zero and negative maximum value -V_o C
Any of these D
None of these E

Question # 9

The phase angle of a series RLC circuit at resonance is

180° A
90° B
0° C
None of the these D

Question # 10

Which of the following diode is used for the detection of light

photo diode A
light emitting diode B
photo voltaic cell C
all of them D

Question # 11

To design a resonant circuit of frequency 100 KHz with an inductor of inductance 5 mH, we need a capacitor of capacitance

5.07 pF A
50 pF B
0.507 pF C
507 pF D

Question # 12

In an A.C circuit with resistor only, the current and voltage have a phase angle of

90° A
0° B
180° C
none of these D

Question # 13

The basic circuit elements of A.C circuit are

Resistor A
Inductor B
Capacitor C
All the three D

Question # 14

At resonance frequency the impedance of parallel resonance circuit is

Maximum A
Minimum B
Zero C
None of the above D

Question # 15

When the p-n junction is forward biased its resistance is of the order of

few mega ohms A
few kilo ohms B
few ohms C
few milli ohms D

Question # 16

During each cycle, alternating voltage reaches a peak value

One time A
Two times B
Four times C
A number of times depending on the frequency D

Question # 17

The emitter-base junction of a transistor is forward-biased and collector-base junction is reverse-biased. If the base current is increased, its

I_cwill decrease A
V_CEwill increase B
I_Cwill increase C
V_CCwill increase D

Question # 18

A signal is amplified at the output without any change of phase, if it is applied at the

inverting input A
non-inverting input B
at any of the input C
none of these D

Question # 19

In a transistor, the central region is called

collector A
emitter B
base C
none of them D

Question # 20

In describing functions of digital systems, a closed switch will be shown as

0 A
1 B
low C
any one of these D

Question # 21

In series RC circuit when R=X_c, then the phase angle is

0° A
90° B
70° C
45° D

Question # 22

The alternative voltage of current is actually measured by:

Its RMS value A
Square root of its mean square value B
Instantaneous value C
Peak value D
Both (A) and (B) E

Question # 23

The most common source of alternating voltage is:

Motor A
Transformer B
AC genrator C
Both (A) and (C) D
Both (A) and (B) E

Question # 24

In RLC series circuit, resonance occurs when

X_{L > Xc} A
X_{L < Xc} B
X_{L = Xc} C
None of these D

Question # 25

A diode characteristic curve is a plot between

current and time A
voltage and time B
voltage and current C
forward voltage and reversed voltage D

Question # 26

The bridge circuit of full wave rectification uses

one diode A
two diode B
three diode C
four diode D

Question # 27

Unless stated otherwise, when we speak of A.C. meter reading, we usualy mean:

Peak value A
RMS value B
Instantaneous value C
Peak-to-peak value D
Both (A) and (C0 E

Question # 28

SI unit of impedance is

hertz A
henry B
ampere C
ohms D

Question # 29

At higher frequency of the alternating current, the capacitive reactance X_c

Increases A
Decreases B
Remains the same C
Increases only when the voltage increases D

Question # 30

A sinusoidally alternating voltage or current can be graphically represented by a:

Vector A
Rotating vector B
Clockwise vector C
Anticlockwise voltage vector D
None of these E

Sr.#	Question	Answer
1	The bridge circuit of full wave rectification uses	A. one diode B. two diode C. three diode D. four diode
2	The entire wave form of sinusoidal voltage is actually a set of all the:	A. Positive maximum value + V_oand negative maximum value -V_o B. Posiotive maximum value +V_oand zero C. Zero and negative maximum value -V_o D. Any of these
3	When the pn-junction is connected reversed biased, its resistance is of the order of	A. few ohms B. few kilo-ohms C. few mega-ohms D. few mili-ohms
4	The value of the input resistance of OP-AMP is of the order of	A. few ohms B. few hundred ohms C. several kilo ohms D. several maga ohms
5	During the positive half-cycle in the half-wave rectification,the diode	A. does not conduct B. conducts C. either of these D. neither of these
6	The basic circuit elements of A.C circuit are	A. Resistor B. Inductor C. Capacitor D. All the three
7	Chock consumes externally small	A. Charge B. Current C. Power D. Potential
8	SI unit of impedance is	A. hertz B. henry C. ampere D. ohms
9	The Instantaneous value of alternative current maybe:	A. The same as its RMS value B. Greater than its Rms value C. The same as its peak value D. Any of these
10	In which of the following diodes when an electron combines with a hole during the forward biasing, photon of visible light is emitted.	A. photo diode B. light emitting diode C. photo voltaic cell D. all of them

Latest Educational News Stories

Pakistan's Largest Database of Colleges and Universities

BS Programs

University Past Papers

University Results

Exam Results 2024

Study Abroad Programs and Opportunities for Pakistani Students

ECAT Pre General Science Physics Chapter 16 MCQ Test With Answer

MCQ's Test For ECAT Pre General Science Physics Chapter 16 Alternating Current

ECAT Pre General Science Physics Chapter 16 Alternating Current

When the pn-junction is in reversed biased, current flows through the junction due to the

For the normal operation of the transistor, its

Average value of A.C voltage during one cycle is

A digital system deals with quantities or variables which have

The open loop gain of OP-AMP is of the order of

The device which allows only the flow of an A.C. through a circuit is

A changing magnetic flux creates around itself

The entire wave form of sinusoidal voltage is actually a set of all the:

The phase angle of a series RLC circuit at resonance is

Which of the following diode is used for the detection of light

To design a resonant circuit of frequency 100 KHz with an inductor of inductance 5 mH, we need a capacitor of capacitance

In an A.C circuit with resistor only, the current and voltage have a phase angle of

The basic circuit elements of A.C circuit are

At resonance frequency the impedance of parallel resonance circuit is

When the p-n junction is forward biased its resistance is of the order of

During each cycle, alternating voltage reaches a peak value

The emitter-base junction of a transistor is forward-biased and collector-base junction is reverse-biased. If the base current is increased, its

A signal is amplified at the output without any change of phase, if it is applied at the

In a transistor, the central region is called

In describing functions of digital systems, a closed switch will be shown as

In series RC circuit when R=Xc, then the phase angle is

The alternative voltage of current is actually measured by:

The most common source of alternating voltage is:

In RLC series circuit, resonance occurs when

A diode characteristic curve is a plot between

The bridge circuit of full wave rectification uses

Unless stated otherwise, when we speak of A.C. meter reading, we usualy mean:

SI unit of impedance is

At higher frequency of the alternating current, the capacitive reactance Xc

A sinusoidally alternating voltage or current can be graphically represented by a:

Prepare Complete Set Wise ECAT Pre General Science Physics Chapter 16 Alternating Current MCQs Online With Answers

Set 1

Set 2

Set 3

Set 4

Topic Test

Top Scorers Of ECAT Pre General Science Physics Chapter 16 Alternating Current MCQ`s Test

ECAT Physics Chapter 16 Important MCQ's

Test Questions

Is this page helpful?

Share your comments & questions here

In series RC circuit when R=X_c, then the phase angle is

At higher frequency of the alternating current, the capacitive reactance X_c