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

Question # 1

SI unit of impedance is

hertz A
henry B
ampere C
ohms D

Question # 2

In a transistor, if the central region is p-type then this type of transistor is known as

p-n-p transistor A
n-p-n transistor B
either of these C
none of these D

Question # 3

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 # 4

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 # 5

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 # 6

In a transistor, if the central region is n-type, then this type of transistor is known as

n-p-n transistor A
p-n-p transistor B
either of these C
none of these D

Question # 7

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 # 8

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 # 9

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

A rectifier A
Detector B
Oscillator C
An amplifier D

Question # 10

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 # 11

The closed loop gain of the inverting amplifier is written as

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

Question # 12

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 # 13

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 # 14

An A.C. voltage is applied across the inductor. When the frequency of the voltage is increased, the current

Decreases A
Increases B
Does not change C
Momentarily goes to zero D

Question # 15

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 # 16

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 # 17

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 # 18

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 # 19

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 # 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

The value of the potential difference across the depletion region for the case of germanium is

0.3 V A
0.5 V B
0.7 V C
0.9 V D

Question # 22

Average value of A.C voltage during one cycle is

1 A
Zero B
Maximum C
Variable D

Question # 23

Transmitting antenna emits

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

Question # 24

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 # 25

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 # 26

In frequency modulation (FM), the carrier waves amplitude

Remains constant A
Increase B
Decreases C
None of these D

Question # 27

The impedance of RLC series resonance circuit at resonant frequency is

Greater than R A
Equal to R B
Less than R C
None of these D

Question # 28

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 # 29

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 # 30

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

Sr.#	Question	Answer
1	The basic circuit element in D.C. circuit is:	A. A capacitor B. A resistor C. An inductor D. Both (A) and (C)
2	The wave form of alternating voltage is the graph between:	A. Voltage across X-axis and time across y-axis B. Current and time C. Voltage along y-axis and time along x-axis D. Voltage and current
3	Which of the following diode is used for the detection of light	A. photo diode B. light emitting diode C. photo voltaic cell D. all of them
4	A P-N juction or semiconductor diode cannot be used as	A. A rectifier B. Detector C. Oscillator D. An amplifier
5	At resonance, the impedance of RLC series circuit is	A. Maximum B. Zero C. Minimum D. Determinate
6	In a normally biased n-p-n transistor, an electron c current I_Eflows from the	A. emitter into the base B. collector into the base C. base into collector D. none of these
7	An A.C. voltmeter read 250 volts. The frequency of alternating is 50 Hz, the peak value of voltage is	A. 3525.0 volts B. 35.35 volts C. 353.5 volts D. 3.535 volts
8	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
9	If we connect a A.C. volt meter to read A.C. voltage, It would read its:	A. RMS value B. Instantaneous value C. Valued average over a cycle D. Zero
10	To design a resonant circuit of frequency 100 KHz with an inductor of inductance 5 mH, we need a capacitor of capacitance	A. 5.07 pF B. 50 pF C. 0.507 pF D. 507 pF

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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