A 3 phase, 4 wire system is commonly used for

a) Primary distribution
b) Secondary distribution
c) Primary transmission
d) Secondary transmission

As per IE rules the maximum allowable variation between declared and actual voltage at consumer' s premises should be

The size of conductor in power cables depends on
a) Operating voltage
b) Power factor
c) Current to be carried
d) Type of insulation used

Single core cables are usually not provided with armouring due
a) Avoid excessive loss in the armour
b) Make the cable more flexible
c) Make the cable more hygroscopic
d) None of these

The safety of electrical appliances and wiring is ensured by
a) Insulation b) Earthing
c) Providing fuse in the electric circuit
d) All of these

Which of the following is least preferred for earthing
a) Clayey soil
b) Dry earth
c) Earth mixed with salt and charcoal
d) None of these

The earthing electrodes should be placed within a distance ofmeter from the  building whose installation system is being earthed.
a) 4.0
b) 0.5
c) 1.5
d) 2.5

The loop earth wire used shall not be of the size less than
a) 8 SWG
b) 10 SWG
c) 20 SWG
d) 14 SWG or half of the size of the sub circuit wire

In an n-type semiconductor, the concentration of minority carriers mainly depends upon the

a) Doping technique
b) Temperature of material
c) Number of donor atoms
d) Quality of the intrinsic

When a normal atom looses an electron. It becomes
a) A positive ion
b) A negative ion
c) Electrically neutral
d) Free to move

One of the way to destroy a diode is
a) To exceed the current limit in forward direction
b) To apply small voltage in the reverse direction
c) To dip it in water
d) To drop on floor

The emf induced in a coil due to change of flux produced by another coil, is called
a) Mutual induced emf
b) M.M.F
c) Self induced emf
d) Dynamically induced emf

A single phase transformer has 600 turns on the primary and 80 turns on the secondary. If   the primary connected to 3300 volt supply. The secondary voltage will be
a) 340 V
b) 540 V
c) 440 V
d) 430 V

Power factor decreases due to
a) Inductive load
b) Resistive load
c) Capacitive load
d) None of these

The insulation resistance between conductors as per IE rule should not be less than
a) 2 Mega-ohm
b) 1 Mega ohm
c) 0.5 Mega ohm
d) 1.5 mega ohm

The size of the continuous earth wire used with cables in domestic installations should not be less than
a) 14 SWG
b) Half of the installation conductor size
c) Both (a) & (b)
d) None of these

Service fuse is used
a) After the energy meter  
b) Before the main switch
c) Both (a) & (b)
d) None of these

What is the resistance of a lamp which draws 120 mA when connected to a 12.6-V battery?
a) 1100
b) 105 Q
c) 120 Q
d) 115 Q

Which of the following wires has the greatest cross-sectional area?
a) 9 SWG
b) 14 SWG
c) 22 SWG
d) 30 SWG

What is the unit of measurement for electrical pressure or electromotive force?
a) Amps
b) Ohms
c) Volts
d) Watts

Which of the following circuit configurations has the same amount of voltage drop across each of its components?
a) Parallel
b) Series-parallel
c) Series
d) Combination

As temperature increases, what happens to the current-carrying ability of wire?
a) There is no change
b) The wire can carry more current
c) The wire can carry less current d) The wire can carry no current of

In a series circuit consisting of 3 resistors of 45Q each and a 50-V source, what is the  approximate amount of heat produced?
a) 16.6 w
b) 18.5 W
c) 135 w
d) 150 W

In a two-branch parallel circuit containing one 300 resistor in each branch and powered from a 10-V source, what is the total current flowing in the circuit?
a) 0.33A
b) 0.67 A
c) 0.40 A
d) 0.60 A

Which of the following determines total power in a series circuit?
 a) Source voltage times the current
b) Total voltage applied to the circuit
 c) Current flowing through a switch
d) Average of the wattage consumed by each resistor

If a resistor suddenly decreases in value (resistance decreases), what will happen to the current through the resistor?
a) Increases
b) Remains unchanged
c) Decreases
d) Fluctuates

What is the applied voltage on a circuit in which 0.5A is flowing and 10 W is generated?
c) 20 v
d) 50 V

What is the classification of an AC circuit in which the capacitive reactance is 50 Q, the inductive reactance is 30Q and the resistance is 100 Q?
a) Resistive
b) Inductive
c) Capacitive
d) Resonant

When using a standard multimeter to measure AC voltage, what type of measurement will the multimeter indicate?
a) Peak to peak
b) Peak
c) Average
d) rms

What happens to current flow in a capacitive circuit when the DC voltage across the capacitor is approximately equal to the source voltage?
a) Current flow is optimized
b) Little current flows
c) Current flow is maximum at the source
d) Current flow is maximum at the capacitor

How many watts are in 100 microwatts?
a) 0.01 milliwatts
b) 0.1 milliwatts
c) 1.0 milliwatts
d) 10 nanowatts

Which of the following is an appropriate use for a voltmeter?
a) To measure difference of potential b) To measure current flow
c) To determine total resistance d) To determine power output

What should be observed when connecting a voltmeter into a DC circuit?
a) rms
b) Resistance
c) Polarity
d) Power factor

The Henry is the unit of measurement for which of the following properties?
a) Reactance
b) Capacitance
c) Resistance
d) Induction

Which of the following devices can be used to test the windings of an inductor for continuity?
a) Wattmeter
b) Voltmeter
c) Ohmmeter
d) Wheatstone bridge

How should a fuse be installed in a circuit to insure proper operation?
a) Parallel to the load
b) Series with the load
c) In any way possible
d) At the ground point

In a parallel circuit operating with a source of 30 VAC, desiY1ed to carry a total current   of 6 A, what happens to the protection device (fuse) when the resistance suddenly changes to 2 Q?
a) Closes
b) No change
c) Shorts to ground
d) Opens

A Wire of resistance R has it length and cross-section both doubled. Its resistance will become
a) O.5R

The resistance of 200W, 200V lamp is
a) 100 Q
b) 200 Q
c) 400 Q  
d) 8000

Which of the following statements does not represent ohm's law?
a) Current/potential difference = constant
b) Potential difference/current = constant
c) Potential difference = current x resistance
d) Current = resistance x potential difference

Which of the following is one of the functions performed by a diode?
a) Filter
b) Amplifier
c) Rectifier
d) Inverter

If a voltmeter reads 112.68 V. If the true value of the voltage is 112.6V, what will be the static error?
a) 0.08V
b) 0.8V
c) 0.6V
d) 0.68 V

A multimeter is used to measure
a) Resistance
b) Current
c) Voltage
d) All of these

What is the desirable feature in an electronic amplifier?
a) High output impedance
b) Low input impedance
c) Good frequency response
d) All of these

A sinusoidal flux .02 wb (max,) links with 55 turns of a transformer secondary coil. The supply frequency is 50 Hz. The rms value of the induced emf in the secondary will be
a) 220 V
b) 244.2 V
c) 440 v
D) 444.2 V

A copductor of length 1 meter moves at right angles to a uniform magnetic field of flux  density 1.5 Wb/m2 with a velocity of 50 m/sec. The induced emf will be
a) 60 V
b) 75 V
c) 70 v
d) 65 V

Which of the following is an ohmic resistor?
a) Diode
b) Germanium
c) Diamond
d) Nichrome
Emf equation of transformer is
a) 4.44 T
b) 4.44 (bf T
d) 4.44 ft

There are terminals in a megger.

Function of Black tape is used at joint of two cables
a) Protect from heat
b) Protect from moisture
c) Increase the mechanical strength
d) None of these

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