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

Question # 1

Average value of A.C voltage during one cycle is

1 A
Zero B
Maximum C
Variable D

Question # 2

Transmitting antenna emits

Magnetic waves A
Electric waves B
Electromagnetic waves C
Sound waves D

Question # 3

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 # 4

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

Question # 5

In free space, the speed of electromagnetic waves is

3 x 10⁸ms^-1 A
3 x 10⁶ms^-1 B
4 x 10⁷ms^-1 C
3 x 10⁹ms^-1 D

Question # 6

Electromagnetic waves transmit energy equal to

1/2 mv² A
m_oc² B
hf/c C
hf D

Question # 7

The bridge circuit of full wave rectification uses

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

Question # 8

In frequency modulation (FM), the carrier waves amplitude

Remains constant A
Increase B
Decreases C
None of these D

Question # 9

At resonance frequency the impedance of parallel resonance circuit is

Maximum A
Minimum B
Zero C
None of the above D

Question # 10

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 # 11

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 # 12

The closed loop gain of the non-inverting amplifier is given by

G = R₂/R₁ A
G = -R₂/R₁ B
G = 1 - R₂/R₁ C
G = 1 + T₂/R₁ D

Question # 13

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 # 14

Alternating current can induce voltage because it has a

High peak value A
Varying magnetic field B
Stronger field than direct curren C
Constant magnetic field D

Question # 15

In a transistor, the central region is called

collector A
emitter B
base C
none of them D

Question # 16

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

Voltage A
Current B
Impedance C
Reactance D

Question # 17

Alternating current is produced by a voltage source which polarity:

Remains the same A
Reverse after period T B
Keeps on reversing with time C
Reverse after every time interval T/2 D
Both (C) and (D) E

Question # 18

Which one of the following waves belongs to electromagnetic spectrum

Radio and TV waves A
Radar waves B
Micro waves C
All of them D

Question # 19

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 # 20

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 # 21

When the pn-junction is forward biased. the current flows through it is of the order of

mili-amperes A
amperes B
nano-amperes C
micro-amperes D

Question # 22

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 # 23

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 # 24

A P-N juction or semiconductor diode cannot be used as

A rectifier A
Detector B
Oscillator C
An amplifier D

Question # 25

The phase angle of a series RLC circuit at resonance is

180° A
90° B
0° C
None of the these D

Question # 26

At resonance, the phase angle for RLC series resonance circuit equals

0° A
90° B
180° C
270° D

Question # 27

The basic circuit element in A.C. circuits are:

Resistor and capacitor A
Resistor and Inductor B
Capacitor only C
Both (B) and (C) D
None of these E

Question # 28

Which of the following has a great concentration of impurity

base A
emitter B
collector C
none of these D

Question # 29

Most OP-AMP operates with

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

Question # 30

The basic circuit elements of A.C circuit are

Resistor A
Inductor B
Capacitor C
All the three D

Sr.#	Question	Answer
1	Which one of the following waves belongs to electromagnetic spectrum	A. Radio and TV waves B. Radar waves C. Micro waves D. All of them
2	For a n-p-n transistor, the conventional current equation can be written as	A. I_E+ I_C= I_B B. I_C- I_B= I_E C. I_C+ I_B= I_E D. I_B+ I_E= I_C
3	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
4	Which one of the following is correct?	A. V_o= 1.414 V_rms B. I_ams= 1.414 I_o C. VO = 10.70 Vrms D. Both a and b
5	At resonance frequency the impedance of parallel resonance circuit is	A. Maximum B. Minimum C. Zero D. None of the above
6	At resonance, the impedance of RLC series circuit is	A. Maximum B. Zero C. Minimum D. Determinate
7	The impedance of RLC series resonance circuit at resonant frequency is	A. Greater than R B. Equal to R C. Less than R D. None of these
8	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
9	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
10	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

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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