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

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 # 3

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 # 4

Most OP-AMP operates with

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

Question # 5

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 # 6

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 # 7

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 # 8

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 # 9

When either L or C is increased, the resonant frequency of the RLC series circuit

Increases A
Decreases B
Remains the same C
Becomes zero D

Question # 10

The power factor of resonant series circuit is

1 A
0 B
-1 C
0.5 D

Question # 11

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 # 12

In a normally biased n-p-n transistor, an electron c current I_Eflows from the

emitter into the base A
collector into the base B
base into collector C
none of these D

Question # 13

In n-p-n transistor, emitter base junction is kept

reversed A
forward biased B
may be reversed or may be forward biased C
none of these D

Question # 14

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 # 15

The phase at the positive peak of an A.C. cycle is:

0º
A
90º
B
180º
C
0 andᏘ D
Ꮨ/2 and 3Ꮨ/2 E

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

When the pn-junction is connected reversed biased, its resistance is of the order of

few ohms A
few kilo-ohms B
few mega-ohms C
few mili-ohms D

Question # 18

OP-AMP has the following input terminals

one A
two B
three C
four D

Question # 19

During the negative half-cycle of the half-wave rectification, the diode

does not conduct A
conducts B
either of these C
none of these D

Question # 20

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 # 21

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 # 22

Conversion of alternating current into direct current is called

amplification A
rectification B
conduction C
polarization D

Question # 23

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 # 24

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 # 25

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 # 26

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 # 27

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 # 28

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 # 29

The value of the input resistance of OP-AMP is of the order of

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

Question # 30

In a transistor, the central region is called

collector A
emitter B
base C
none of them D

Sr.#	Question	Answer
1	The open loop gain of OP-AMP is of the order of	A. 10² B. 10³ C. 10⁴ D. 10⁵
2	Mathematical manipulation of the two quantized states can be best carried if they are represented by	A. high - low B. yes - no C. on - off D. 0 - 1
3	The average of A.C. current and voltage over a complete cycle is	A. Maximum B. zero C. Neither zero nor maximum D. None of these
4	A signal is amplified at the output without any change of phase, if it is applied at the	A. inverting input B. non-inverting input C. at any of the input D. none of these
5	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
6	In an A.C circuit with resistor only, the current and voltage have a phase angle of	A. 90° B. 0° C. 180° D. none of these
7	Conversion of alternating current into direct current is called	A. amplification B. rectification C. conduction D. polarization
8	The magnitude of alternative voltage V:	A. Always increase B. Always decrease C. Remains constant D. Does not remain constant
9	In half wave rectification	A. both halves of the input voltage is used B. only one half of the input voltage is used C. either of these D. none of these
10	Alternating current can induce voltage because it has a	A. High peak value B. Varying magnetic field C. Stronger field than direct curren D. Constant magnetic field

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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