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

Question # 1

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 # 2

In half wave rectification

both halves of the input voltage is used A
only one half of the input voltage is used B
either of these C
none of these D

Question # 3

The circuit which is used to smooth the output voltage of the full-wave rectification is known as

transformer A
rectifier B
filter C
none of these D

Question # 4

Which one of the following is correct?

V_o= 1.414 V_rms A
I_ams= 1.414 I_o B
VO = 10.70 Vrms C
Both a and b D

Question # 5

Most OP-AMP operates with

+ 6 V supply A
+ 10 V supply B
+ 12 V supply C
+ 24 V supply D

Question # 6

The magnitude of alternative voltage V:

Always increase A
Always decrease B
Remains constant C
Does not remain constant D
None of these E

Question # 7

SI unit of impedance is

hertz A
henry B
ampere C
ohms D

Question # 8

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 # 9

The r.m.s. value of alternating current is equal to its maximum value at angle of

60° A
45° B
30° C
90° D

Question # 10

At resonance frequency the impedance of parallel resonance circuit is

Maximum A
Minimum B
Zero C
None of the above D

Question # 11

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

0° A
90° B
70° C
45° D

Question # 12

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 # 13

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 # 14

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 # 15

A signal appears after amplification, at the output terminal with a phase shift of 180° , if it is applied at

inverting input A
non-inverting input B
any one of the input terminal C
none of them D

Question # 16

The value of current gain of n-p-n transistor is of the order of

tens A
hundreds B
thousands C
ten thousands D

Question # 17

When the emitter-base junction of a transistor is reverse biased, collector current

Reverses A
Increases B
Decreases C
Stops D

Question # 18

Mathematical manipulation of the two quantized states can be best carried if they are represented by

high - low A
yes - no B
on - off C
0 - 1 D

Question # 19

Peak value of alternative current is:

one of its Instantaneous value A
Equal to its RMS value B
The same as its peak-to-peak value C
Both (B) and (C) D
None of these E

Question # 20

The average of A.C. current and voltage over a complete cycle is

Maximum A
zero B
Neither zero nor maximum C
None of these D

Question # 21

If we connect a A.C. volt meter to read A.C. voltage, It would read its:

RMS value A
Instantaneous value B
Valued average over a cycle C
Zero D
Both (B) and (C) E

Question # 22

During the positive half-cycle in the half-wave rectification,the diode

does not conduct A
conducts B
either of these C
neither of these D

Question # 23

If 250V is the RMS value of alternative voltage, then its peak value V_owill be:

353.5V A
250V B
175V C
zero D
400V E

Question # 24

An A.C. voltmeter read 250 volts. The frequency of alternating is 50 Hz, the peak value of voltage is

3525.0 volts A
35.35 volts B
353.5 volts C
3.535 volts D

Question # 25

The highest value reached by the voltage or current:

In quarter cycle is called Instantaneous value A
In half cycle is called peak-to-peak value B
In one cycle is called peak value C
In half cycle is called Instantaneous value D
None of these E

Question # 26

If we connected the ordinary DC ammeter to measure alternating current, it would measure its:

Instantaneous value A
RMS value B
Value averaged over a cycle C
Either (B) or (C) D
Either (A) or (C) E

Question # 27

The sum of positive and negative peak values is called:

Instantaneous value A
Peak value B
Rms valuie C
Peak-to peak-value D
None of these E

Question # 28

For normal operation of transistor, the batteries

V_CCis of much lower value than V_BB A
V_CCis of much higher value than V_BB B
V_{CC is equal to}V_BB C
none of these D

Question # 29

Due to the high value of the input resistance, practically, the value of the current which flows between the input terminals is

zero A
small B
large C
very large D

Question # 30

When electrons in the transmitting antenna vibrate 94000 time per second, they produce radiowaves having frequency

9.4 kHz A
940 kHz B
94 kHz C
None of these D

Sr.#	Question	Answer
1	At higher frequency of the alternating current, the capacitive reactance X_c	A. Increases B. Decreases C. Remains the same D. Increases only when the voltage increases
2	Electromagnetic waves transmit energy equal to	A. 1/2 mv² B. m_oc² C. hf/c D. hf
3	The value of output resistance of OP-AMOP is of the order of	A. few ohms B. few hundred ohms C. several kilo ohms D. several mega ohms
4	The device which allows only the flow of an A.C. through a circuit is	A. Capacitor B. Inductor C. D.C. motor D. Battery
5	When electrons in the transmitting antenna vibrate 94000 time per second, they produce radiowaves having frequency	A. 9.4 kHz B. 940 kHz C. 94 kHz D. None of these
6	Due to the high value of the input resistance, practically, the value of the current which flows between the input terminals is	A. zero B. small C. large D. very large
7	The R₁= infinity and R₂= 0, then the gain of non-inverting amplifier is	A. zero B. infinity C. one D. any one of these
8	SI unit of impedance is	A. hertz B. henry C. ampere D. ohms
9	The closed loop gain of the non-inverting amplifier is given by	A. G = R₂/R₁ B. G = -R₂/R₁ C. G = 1 - R₂/R₁ D. G = 1 + T₂/R₁
10	Transmitting antenna emits	A. Magnetic waves B. Electric waves C. Electromagnetic waves D. Sound waves

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

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

In half wave rectification

The circuit which is used to smooth the output voltage of the full-wave rectification is known as

Which one of the following is correct?

Most OP-AMP operates with

The magnitude of alternative voltage V:

SI unit of impedance is

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

The r.m.s. value of alternating current is equal to its maximum value at angle of

At resonance frequency the impedance of parallel resonance circuit is

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

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

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

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

A signal appears after amplification, at the output terminal with a phase shift of 180° , if it is applied at

The value of current gain of n-p-n transistor is of the order of

When the emitter-base junction of a transistor is reverse biased, collector current

Mathematical manipulation of the two quantized states can be best carried if they are represented by

Peak value of alternative current is:

The average of A.C. current and voltage over a complete cycle is

If we connect a A.C. volt meter to read A.C. voltage, It would read its:

During the positive half-cycle in the half-wave rectification,the diode

If 250V is the RMS value of alternative voltage, then its peak value Vowill be:

An A.C. voltmeter read 250 volts. The frequency of alternating is 50 Hz, the peak value of voltage is

The highest value reached by the voltage or current:

If we connected the ordinary DC ammeter to measure alternating current, it would measure its:

The sum of positive and negative peak values is called:

For normal operation of transistor, the batteries

Due to the high value of the input resistance, practically, the value of the current which flows between the input terminals is

When electrons in the transmitting antenna vibrate 94000 time per second, they produce radiowaves having frequency

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

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

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

If 250V is the RMS value of alternative voltage, then its peak value V_owill be: