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

Question # 1

For a n-p-n transistor, the conventional current equation can be written as

I_E+ I_C= I_B A
I_C- I_B= I_E B
I_C+ I_B= I_E C
I_B+ I_E= I_C D

Question # 2

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 # 3

A changing magnetic flux creates around itself

An electromotive force A
An electric field (changing electric flux) B
Magnetic field C
None of the above D

Question # 4

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 # 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

In frequency modulation (FM), the carrier waves amplitude

Remains constant A
Increase B
Decreases C
None of these D

Question # 7

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 # 8

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 # 9

The basic circuit elements of A.C circuit are

Resistor A
Inductor B
Capacitor C
All the three D

Question # 10

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 # 11

A digital system deals with quantities or variables which have

only one state A
only two discrete states B
three discrete states C
four discrete states D

Question # 12

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 # 13

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 # 14

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 # 15

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

Reverses A
Increases B
Decreases C
Stops D

Question # 16

Most OP-AMP operates with

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

Question # 17

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 # 18

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 # 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

In which of the following components, pn-junction is used

light emitting diode A
photo diode B
photo voltaic cell C
all 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

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 # 23

The bridge circuit of full wave rectification uses

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

Question # 24

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 # 25

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 # 26

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 # 27

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 # 28

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 # 29

The phase angle of a series RLC circuit at resonance is

180° A
90° B
0° C
None of the these D

Question # 30

The time interval during which the Voltage source changes its polarity once is known as:

Time period T A
Half the time period B
Quarter the time period C
Two third of the time period D
None of these E

Sr.#	Question	Answer
1	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
2	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
3	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
4	The value of current gain of n-p-n transistor is of the order of	A. tens B. hundreds C. thousands D. ten thousands
5	In series RC circuit when R=X_c, then the phase angle is	A. 0° B. 90° C. 70° D. 45°
6	A changing magnetic flux creates around itself	A. An electromotive force B. An electric field (changing electric flux) C. Magnetic field D. None of the above
7	During the negative half-cycle of the half-wave rectification, the diode	A. does not conduct B. conducts C. either of these D. none of these
8	The entire wave form of sinusoidal voltage is actually a set of all the:	A. Positive maximum value + V_oand negative maximum value -V_o B. Posiotive maximum value +V_oand zero C. Zero and negative maximum value -V_o D. Any of these
9	The alternative voltage of current is actually measured by:	A. Its RMS value B. Square root of its mean square value C. Instantaneous value D. Peak value
10	The circuit which is used to smooth the output voltage of the full-wave rectification is known as	A. transformer B. rectifier C. filter D. none of these

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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