ELECTRICAL CIRCUITS Multiple Choice Questions Part 1

1 Conventional flow assumes charges flow from
Positive to negative
Positive to positive
⦁ Negative to positive
⦁ Negative to negative

2 Series resonance occurs when
⦁  XL = XC
⦁  XL = R
Z = R
Both A and C

3 The symbol Q refers to
Resonance quotient
Quality factor
Power quotient
Qualification test

4 Electron flow assumes charges flow from
Negative to positive
Negative to negative
Positive to negative
Positive to positive

5 The ratio of W/VA in an ac circuit means
Power factor
Reactive factor
Quality factor

6 At what frequency will an inductor of 5mH have the same reactance as a capacitor of 0.1 µF?
7.12 kHz
7.12 Hz
7.12MHz
7.12 GHz

7 Property of an electric circuit that dissipates electric energy
Reactance
Impedance
Resistance
Conductance

8 In a resonant circuit, if Q ≤ 10 resonant frequency bandwidth.
Bisects
Exceeds
Is less than
Is equal to

9 Which of the following conditions is not true for a series RLC circuit at resonance?
Z = jXL
XL = XC
The power factor is one
The magnitude of Z is ƒR2 + (XL — XC)2

10 A tank circuit is a
Parallel LC circuit
Series LC circuit
A resonant circuit
A non-resonant circuit

11 A capacitive load always has a power facto
Lagging
Zero
Unity

12 Which is considered as the effect of a dielectric material?
Increasing capacitance
Decreasing capacitance
Reducing the working voltage
Increasing the distance between the plates

13 The  open-circuit  voltage  at  the  terminal  of load  RL is 60V. Under the condition of maximum power transfer, the load voltage will be
60 V
15 V
20 V
30 V

14 Which statement is true?
A series resonant circuit is of high impedance
A parallel resonant circuit is of low impedance
A series resonant circuit is inductive if it operates at a frequency higher than the resonant frequency
A parallel resonant circuit is inductive if it operates at a frequency higher than the resonant frequency

15 What is considered as the most important value of a sine wave?
Effective value
Peak value
Average value
Instantaneous value

16 The value of temperature coefficient (a) is dependent upon
The nature of material and temperature
The length of material
The cross-sectional area of the material
The volume of the material

17 At what frequency will the current in a series RLC circuit reach its maximum value for an applied voltage of 15 V with R = 500 fi, L = 100 µH and C = 0.001 µF?
503 kHz
403 kHz
603 kHz
303 kHz

18 Which of the following does not affect resistance?
Resistivity
Cross-sectional area
Mass
Length

19 Which of the following is not considered a physical factor affecting resistance?
Length
Material type
Temperature
Cross-sectional

20 The graph between an alternating quantity and time is called
Sine wave
Curve
Waveform
A plot

21 Which of the following is the most popular waveform?
Sinusoidal
Square wave
Triangular
Sawtooth

22 What is the reciprocal of quality factor?
Power factor
Reactive factor
Dissipation factor
1/Q factor

23 In liquids and gases, ionization current results from a flow of
Positive or negative ions
Free electrons
Ions that are lighter in weight than electrons
Protons

24 VL = VC in a series RLC circuit when
The value of the impedance is minimum
The power factor is zero
The current leads the total voltage by 90˚
The total voltage is zero

25 An ac series circuit is composed of a resistance of 20 fi, inductive reactance of 40 fi, and a capacitive reactance of 15 fi. If a current of 1 ampere is flowing, what is the applied voltage
320 V
32 V
220 V
22 V

26 An intermittent and non-symmetrical alternating current like that obtained from the secondary winding of an induction coil
Transient ac current
Inductive current
Capacitive current

27 If two equal resistances connected in series across a certain supply are now connected in parallel across the same supply,  the  power  produced  will  be that of series connection
One-half
One-fourth
Two times
Four times

28 Transient period is considered over after
5 v
1 v
100 v
6 v

29 What rating of a resistor determines its ability to absorb heat?
Wattage
Ohmic
Current
Voltage

30 A capacitance of 6 µµF means
6 pF
6 nF
6 fF
6 aF

31 The voltage cannot be exactly in phase with the current in a circuit that contains
Only capacitance
Only resistance
Inductance and capacitance
Inductance, capacitance and resistance

32 The charge in the capacitor is stored at the
Terminals
Plates
Dielectric
Air

33 The reactance curve is a plot of frequency versus for a series RLC circuit
Current
Voltage
Gain
Impedance

34 What is the other name of relative permittivity?
Dielectric strength
Breakdown voltage
Specific inductance capacity

35 In a series RLC circuit
The current lags VL by 90˚
The current leads VL by 90˚
Z = jXL at resonance

36 Resistor with colored bands in the body
Wire-wound resistor
Carbon-composition resistor
Potentiometer
Rheostat

37 What is the resonant frequency of a circuit when L of 25 microhenrys and C of 10 picofarads are in parallel?
10.1 kHz
10.1 MHz
101 MHz
101 kHz

38 And ideal current source has an internal conductance of siemen(s)
Infinite
One
Zero
One million

39 For a series circuit, the higher the quality factor
The greater the bandwidth
The narrower the passband
The wider the passband

40 Which of the following is a common material used in wire-wound resistors?
Manganin
Carbon
Bronze
German silver wire

41 If one resistance in a series connection is open, then
The current is zero in all the other resistances
The current is maximum in all the other resistances
The voltage is zero across the open resistance
The voltage is infinite across the open resistance

42 What determines the magnitude of electric current?
The rate at which electrons are produced
The type of material used
The current carrying capacity of the circuit
The rate at which electrons pass a given point

43 Which of the following is neither a basic physical law nor deliverable from one?
Ohm’s law
Coulomb’s law
Kirchhoff’s first law
Kirchhoff’s second law

44 Another term for superconductor.
Generic conductor
Ultraconductor
Cryotron
Cryogenic conductor

45 A circuit whose parameters change with voltage or current.
Non-linear circuit
Linear circuit
Complex circuit
Passive circuit

46 Another term of the quality factor of the resonant circuit.
Figure of merit
Figure of demerit
Noise factor
Noise figure

47 Which of the following represents the energy stored in a capacitor?
CV2/2
2Q2/C
C2/V
CV

48 What theorem is usually used in the analysis of transistor circuit?
Superposition theorem
Millman’s theorem
Thevenin’s theorem
Norton’s theorem

49 Which of the following capacitors has the highest cost per µF?
Plastic
Air
Mica
Electrolytic

50 Under the conditions of maximum power transfer, a voltage source is delivering a
power of 15 W to the load. What is the power generated by the source?
60 W
30 W
15 W
4 W