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Browse complete papersFor the circuit shown in the figure, the current through the resistor R2 is ___________.
2 mA
1.8 mA
2.8 mA
4 mA
Correct answer
2 mA
For supplying a large three-phase load with neutral connection requirement, which transformer connection is generally preferred?
Delta-delta connection for single-phase domestic lighting systems
Star-star connection with neutral grounding arrangement on both sides
Scott connection for operation of balanced three-phase motor loads
Open delta connection for reduction of transformer copper losses
Correct answer
Delta-delta connection for single-phase domestic lighting systems
A PNP transistor is fabricated with an increased base doping concentration while keeping all other physical dimensions and doping levels constant. What is the effect on the transistor's performance?
The common-emitter current gain decreases
The emitter injection efficiency increases
The base transport factor increases.
The collector current becomes independent of emitter current
Correct answer
The common-emitter current gain decreases
In a three-phase induction motor, the phasor diagram shows an angle between the applied stator voltage and the resulting stator current. This angle primarily indicates:
Rotor frequency
Synchronous speed
Rotor slip
Input power factor
Correct answer
Rotor frequency
In a single-phase RL circuit, the RMS voltage across the supply is 100 V, the RMS current is 5 A, and the current lags the voltage by 60°. Determine the apparent power of the circuit.
400 VA
250 VA
500 VA
200 VA
Correct answer
400 VA
In a radial distribution system, which factor causes an increase in voltage drop?
Increase in load current
Decrease in distance
Decrease in resistance
Increase in insulation
Correct answer
Increase in load current
What is an advantage of a bridge rectifier over a center-tapped full-wave rectifier?
A bridge rectifier produces a higher ripple factor at the output
A bridge rectifier uses only half of the transformer secondary winding
A bridge rectifier can operate using diodes with lower peak inverse voltage rating
A bridge rectifier requires fewer diodes for rectification
Correct answer
A bridge rectifier produces a higher ripple factor at the output
In a closed electrical loop supplied by 10 V, two resistors produce voltage drops of 6 V and 4 V, respectively. Which statement correctly expresses Kirchhoff’s Voltage Law for this loop?
The source voltage is greater than the total voltage drop
The current through the two resistors is different
The source voltage is less than the total voltage drop
The algebraic sum of all voltages around the loop is zero
Correct answer
The source voltage is greater than the total voltage drop
Which Law illustrates the relationship between induced electromotive force (EMF) and the time variation of magnetic flux in a coil?
Columb's Law
Faraday Law of Induction
Ampere Circuital Law
Lenz's Law
Correct answer
Columb's Law
Which method is commonly used to reduce earth resistance in an electrical installation?
Increasing the supply voltage
Increasing the number of earth electrodes
Reducing the size of the earth conductor
Using a higher-rated fuse
Correct answer
Increasing the supply voltage