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

Question # 1

The wave form of alternating voltage is the graph between:

Voltage across X-axis and time across y-axis A
Current and time B
Voltage along y-axis and time along x-axis C
Voltage and current D
Either (B) or (D) E

Question # 2

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

10² A
10³ B
10⁴ C
10⁵ D

Question # 3

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 # 4

Average value of A.C voltage during one cycle is

1 A
Zero B
Maximum C
Variable D

Question # 5

The amplifier which us used to perform mathematical operations electronically is known as

calculator A
OP-AMP B
computer C
any one of them D

Question # 6

When a transistor is used as a switch the circuit in which the current is to be switched OFF and ON, is connected between the

base and emitter A
collector and emitter B
base and collector C
any one of these D

Question # 7

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 # 8

The power factor of resonant series circuit is

1 A
0 B
-1 C
0.5 D

Question # 9

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 # 10

The output voltage of half wave rectification is in the form of

a smooth curve A
a smooth wave B
pulses C
all of the above D

Question # 11

In which of the following diodes when an electron combines with a hole during the forward biasing, photon of visible light is emitted.

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

Question # 12

The Instantaneous value of alternative current maybe:

The same as its RMS value A
Greater than its Rms value B
The same as its peak value C
Any of these D
None of these E

Question # 13

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 # 14

The waveform of alternating voltage is a:

Square A
Rectangular B
Saw-tooth C
Sinusoidal D
None of these E

Question # 15

A resonance curve for RLC series circuit is a plot of frequency versus

Voltage A
Current B
Impedance C
Reactance D

Question # 16

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 # 17

Which of the following diodes can operate in the reverse biased condition

photo diode A
light emitting diode B
photo voltaic cell C
none of these D

Question # 18

The phase angle of a series RLC circuit at resonance is

180° A
90° B
0° C
None of the these D

Question # 19

The R₁= infinity and R₂= 0, then the gain of non-inverting amplifier is

zero A
infinity B
one C
any one of these D

Question # 20

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

Question # 21

The RMS value of alternating current is:

0.7 times at the peak value A
0.5 times the peak value B
0.7 times the Instantaneous value C
Equal to maximum voltage D
None of these E

Question # 22

If the value of C in a series RLC circuit is increased, the resonant frequency

Is not affected A
Increase B
Remains the same C
Decreases D

Question # 23

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 # 24

Conversion of alternating current into direct current is called

amplification A
rectification B
conduction C
polarization D

Question # 25

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

0° A
90° B
70° C
45° D

Question # 26

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 # 27

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 # 28

Alternating current can be transmitted:

To long distance A
At very high cost B
At very low cost C
Both (A) and (C) D
Both (A) and (B) E

Question # 29

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

Question # 30

The value of output resistance of OP-AMOP is of the order of

few ohms A
few hundred ohms B
several kilo ohms C
several mega ohms D

Sr.#	Question	Answer
1	The amplifier which us used to perform mathematical operations electronically is known as	A. calculator B. OP-AMP C. computer D. any one of them
2	The magnitude of alternative voltage V:	A. Always increase B. Always decrease C. Remains constant D. Does not remain constant
3	An A.C. voltage is applied across the inductor. When the frequency of the voltage is increased, the current	A. Decreases B. Increases C. Does not change D. Momentarily goes to zero
4	Conversion of alternating current into direct current is called	A. amplification B. rectification C. conduction D. polarization
5	If 250V is the RMS value of alternative voltage, then its peak value V_owill be:	A. 353.5V B. 250V C. 175V D. zero
6	The value of the potential difference across the depletion region for the case of germanium is	A. 0.3 V B. 0.5 V C. 0.7 V D. 0.9 V
7	When either L or C is increased, the resonant frequency of the RLC series circuit	A. Increases B. Decreases C. Remains the same D. Becomes zero
8	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
9	The value of current gain of n-p-n transistor is of the order of	A. tens B. hundreds C. thousands D. ten thousands
10	A resonance curve for RLC series circuit is a plot of frequency versus	A. Voltage B. Current C. Impedance D. Reactance

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ECAT Pre General Science Physics Chapter 16 MCQ Test With Answer

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