Match the following : (i) Buckling (a) Sediments falling from the plate (ii) Hard Sulphation (b) Bending of electrodes (iii) Partial short (c) High internal resistance of electrodes

C) (i)-(b), (ii)-(c), (iii)-(a)

100 questions with answersProvisional keyEnglish

Electricity Worker - KSEB question paper 2026

Date of test: 30-Sep-2026
Question paper code: 89/26
Category No.: 021/2026
Questions: 100
Answer key: Provisional Answer Key
Exam mode: OMR (pen and paper)

Provisional key. Kerala PSC can change answers after reviewing complaints; the final key decides the marks.

See questions with answers Practise as a mock test

Source: Kerala PSC (keralapsc.gov.in) · official document· Last updated 6 Nov 2026· How we check content· ⚑ Report a problem

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All 100 questions with answers

Tap an option to check yourself, or open the answer. Answers follow the official Kerala PSC answer key.

1.
Which is the unit of electromotive force?
Show answer and explanation
Answer: B —
Volt
The unit of electromotive force (EMF) is the Volt.
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2.
The mass of Proton is how many times the mass of an electron?
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Answer: A —
1840
The mass of a proton is approximately 1840 times the mass of an electron.
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3.
Which one of the following is a good conductor?
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Answer: C —
Eureka
Eureka (a copper-nickel alloy) is a conductor, whereas silicon is a semiconductor and paper/mica are insulators.
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4.
Which colour is used for earthing wires?
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Answer: D —
Green
Green or Green-Yellow is the standard color for earthing wires.
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5.
In Tinman’s solder the composition of Lead and Tin is :
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Answer: A —
Tin – 50% Lead – 50%
Tinman's solder typically consists of 50% Tin and 50% Lead.
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6.
Which is the working temperature of Electrician’s solder?
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Answer: B —
185 ° C
Electrician's solder (fine solder) typically has a melting point around 185 °C.
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7.
How many electrons are passing through a conductor for one Ampere current?
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Answer: C —
6.24 × 10^{18} electrons
One Ampere is defined as one Coulomb per second, and one Coulomb is approximately $6.24 \times 10^{18}$ electrons.
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8.
Which is the unit of resistance?
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Answer: D —
Ohm
The SI unit of electrical resistance is the Ohm ( $\Omega$ ).
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9.
Which of the following is the Atomic number of silicon?
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Answer: B —
14
Silicon has an atomic number of 14.
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10.
Which is the unit of resistivity?
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Answer: A —
Ohm – Meter
The SI unit of electrical resistivity is Ohm-meter ( $\Omega \cdot m$ ).
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11.
In any closed circuit at constant temperature, the ratio of voltage and current :
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Answer: C —
Remains constant
According to Ohm's Law ( $V = IR$ ), the ratio $\frac{V}{I} = R$ , which remains constant for a metallic conductor at constant temperature.
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12.
Calculate the current I in the circuit : 🔍 Click to zoom
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Answer: B —
1 A
Based on the circuit parameters provided in the diagram, the calculated current is 1 A.
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13.
In the circuit diagram shown, if V S = 20 V, V 1 = 5 V and V 2 = 5 V, what will be the value of V3? 🔍 Click to zoom
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Answer: B —
10 V
In a series circuit, $V_S = V_1 + V_2 + V_3$ . Thus, $20 = 5 + 5 + V_3$ , which gives $V_3 = 10 V$ .
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14.
Resistance of carbon increases if :
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Answer: A —
Temperature is reduced
Carbon is a semiconductor/non-metal with a negative temperature coefficient of resistance, meaning its resistance increases as temperature decreases.
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15.
If the length of a wire is doubled and area of cross section is halved, then new resistance will be :
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Answer: C —
Increases 4 times
Resistance $R = \rho \frac{L}{A}$ . If $L' = 2L$ and $A' = \frac{A}{2}$ , then $R' = \rho \frac{2L}{A/2} = 4 \times \rho \frac{L}{A} = 4R$ .
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16.
Find the odd one out : Lead acid cell, Nickel-iron cell, Carbon-Zinc cell
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Answer: C —
Carbon-Zinc cell
Carbon-Zinc is a primary cell, while Lead-acid and Nickel-iron are secondary (rechargeable) cells.
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17.
If a group of 4 cells are connected in parallel, each cell has a rating 1.5 V and 2 AH. The voltage rating of this battery would be :
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Answer: D —
1.5 V
In a parallel connection, the voltage remains the same as that of a single cell, while the capacity (AH) increases.
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18.
Match the following : (i) Buckling (a) Sediments falling from the plate (ii) Hard Sulphation (b) Bending of electrodes (iii) Partial short (c) High internal resistance of electrodes
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Answer: C —
(i)-(b), (ii)-(c), (iii)-(a)
Buckling refers to the bending of electrodes, Hard Sulphation leads to high internal resistance, and partial short is caused by sediments.
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19.
Which of the following statement is / are correct about care and maintenance of batteries? (i) The level of electrolyte should always be kept to a minimum of 10 mm below the plates (ii) A discharged battery should be tested with a high rate discharge tester (iii) If the battery has not been used for a long period then the battery should be put on a trickle charge (iv) The vent plugs should be kept open while charging
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Answer: A —
Only (iii) and (iv)
Statements (iii) and (iv) are standard maintenance practices for lead-acid batteries.
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20.
The specific resistance of conductors is :
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Answer: B —
Low
Conductors are characterized by having low specific resistance (resistivity) to allow current flow.
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21.
Which of the following statement is/are correct about magnetic materials? (i) The materials such as iron, steel, nickel, cobalt and their alloys are ferromagnetic materials (ii) Soft iron become permanent magnet and steel become temporary magnet after magnetization (iii) Materials which are slightly attracted by a powerful magnet are called paramagnetic materials (iv) Water is paramagnetic and air is diamagnetic
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Answer: B —
Only (i) & (iii)
Statement (i) and (iii) are correct. Soft iron is used for temporary magnets, and steel for permanent magnets (reversing statement ii).
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22.
Which of the following statement is/are correct about magnetic lines of force? (i) The magnetic lines of force travel from South to North pole outside the magnet and North to South pole inside the magnet. (ii) The magnetic lines of force never intersect each other (iii) The magnetic lines of force preferred to travel through nonmagnetic materials (iv) The magnetic lines of force forms a loop
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Answer: C —
Only (ii) & (iv)
Magnetic lines of force never intersect and form closed loops. They travel N to S outside and S to N inside.
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23.
Commercial method of making permanent magnet is
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Answer: D —
Induction method
The electrical induction method is the most efficient and common commercial method for magnetizing materials.
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24.
Which of the following statement is/are correct about different methods to find the direction of magnetic field? (i) The Right Hand Grip Rule can be used to determine the direction of the magnetic field in current carrying conductor (ii) The right handed corkscrew rule used to determine the direction of magnetic field in the solenoid (iii) Direction of magnetic field in a solenoid can be found by using right hand palm rule (iv) In right hand palm rule the thumb indicates the direction of North pole in the solenoid
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Answer: D —
Only (i), (iii) and (iv)
Statements (i), (iii), and (iv) correctly describe the rules for determining magnetic field direction.
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25.
Match the following List A (Quantity) with List B (Unit) : List A (i) MMF (ii) Reluctance (iii) Magnetic field strength (iv) Magnetic flux density List B (1) Tesla (2) AT/m (3) AT (4) AT/Wb
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Answer: A —
(i)-(3), (ii)-(4), (iii)-(2), (iv)-(1)
MMF is in Ampere-Turns (AT), Reluctance is AT/Wb, Magnetic field strength is AT/m, and Flux density is Tesla.
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26.
Which of the following statement is/are not correct about Hysteresis and Hysteresis loop? (i) Hysteresis is the lagging of magnetic flux density (B) behind the magnetizing force (H) during magnetization and demagnetization of a magnetic material (ii) Hysteresis loop of soft iron is narrow, whereas hysteresis loop of hard steel is wide (iii) Hysteresis loss of a magnetic material is inversely proportional to the area of hysteresis loop (iv) The hysteresis loop of soft iron is narrow because it has low coercivity and low retentivity
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Answer: C —
Only (iii)
Hysteresis loss is directly proportional to the area of the hysteresis loop, not inversely proportional.
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27.
The energy stored in an inductor is :
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Answer: B —
Stored in the magnetic field surrounding the inductor
Inductors store energy in the form of a magnetic field when current flows through them.
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28.
Which of the following statement is/are correct about inductive reactants? (i) Inductive reactants $X_L = 6.28 f L \Omega$ (ii) Inductive reactants in DC circuit is greater than that of AC circuits (iii) Inductive reactants is the result of emf of the inductor (iv) Parallel connection of inductors reduces the inductive reactants
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Answer: C —
Only (i), (iii) and (iv)
Inductive reactance $X_L = 2\pi fL$ . In DC, $f=0$ , so $X_L=0$ . Parallel connection reduces total inductance and thus reactance.
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29.
Time constants of RL circuit and RC circuit are given by
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Answer: A —
L/R and RC Respectively
The time constant $\tau$ for an RL circuit is $\frac{L}{R}$ and for an RC circuit is $RC$ .
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30.
Which of the following statement is/are not correct about capacitors? (i) Capacitance of parallel plate capacitor is increases with its plate area (ii) Coulomb per volt is a unit of capacitance (iii) Energy stored in a capacitor is given by $W = 0.5 CV^2$ (iv) Capacitors are connected in series to increase the effective capacitance
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Answer: D —
Only (iv)
Connecting capacitors in series decreases the effective capacitance; they are connected in parallel to increase it.
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31.
One complete set of positive and negative values of an alternating quantity is called :
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Answer: B —
Cycle
A cycle is defined as one complete set of positive and negative values of an alternating quantity.
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32.
The RMS value of AC is also known as :
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Answer: B —
Effective value
RMS (Root Mean Square) value is equivalent to the DC value that produces the same heating effect, hence called the effective value.
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33.
The value of form factor for a pure sine wave is approximately :
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Answer: C —
1.11
Form factor = RMS value / Average value = $\frac{I_m/\sqrt{2}}{2I_m/\pi} \approx 1.11$ .
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34.
Peak factor (crest factor) of a sine wave is :
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Answer: B —
1.414
Peak factor = Peak value / RMS value = $\frac{I_m}{I_m/\sqrt{2}} = \sqrt{2} \approx 1.414$ .
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35.
Which of the following statement is/are correct about AC circuit? (i) In a purely resistive AC circuit, current and voltage are in phase (ii) In a purely inductive AC circuit, current lags voltage by 90° (iii) In a purely capacitive AC circuit, current leads voltage by 180°
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Answer: B —
Only (i) & (ii)
In a purely capacitive circuit, current leads voltage by 90°, not 180°.
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36.
Power factor of an AC circuit is defined as the cosine of the angle between :
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Answer: C —
Voltage and current
Power factor is defined as $\cos \phi$ , where $\phi$ is the phase angle between voltage and current.
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37.
The main advantage of AC over DC for power transmission is :
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Answer: B —
AC voltage can be easily stepped up/down using transformers
Transformers allow AC voltage to be stepped up for efficient long-distance transmission and stepped down for safe usage.
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38.
True power in an AC circuit is measured in :
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Answer: C —
Watt
True power (active power) is measured in Watts, while apparent power is in VA and reactive power in VAR.
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39.
Earthing means connecting the :
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Answer: B —
Non-current carrying metal parts of equipment to the general mass of earth
Earthing provides a low-resistance path to the ground for fault currents to ensure safety.
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40.
The maximum permissible value of earth resistance for domestic installations is generally :
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Answer: B —
Less than 5 ohms
For domestic installations, the earth resistance should ideally be low, typically less than 5 ohms.
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41.
In Flemings right hand rule, what does the forefinger represent?
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Answer: C —
The direction of flux
In Fleming's Right Hand Rule, the forefinger points in the direction of the magnetic field (flux).
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42.
In DC series generator, the field winding has :
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Answer: B —
Few turns of thick wire
Series field windings carry full load current, so they are made of few turns of thick wire to minimize resistance.
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43.
The EMF equation of a DC generator is :
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Answer: D —
$E = \frac{\phi Z N P}{60A}$
The standard EMF equation for a DC generator is $E = \frac{\phi Z N P}{60A}$ .
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44.
The field winding of a shunt generator consist of :
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Answer: C —
Many turns of thin wire
Shunt field windings are connected in parallel with the armature and require high resistance, hence many turns of thin wire.
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45.
Which type of compound generator is used, when the load is located very far from the generator?
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Answer: D —
Over compounded
Over-compounded generators are used to compensate for the voltage drop in long transmission lines.
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46.
Calculate the back emf of a 220 V DC motor with an armature resistance of 0.4 ohm and a full load armature current of 25A :
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Answer: A —
210 V
$E_b = V - I_a R_a = 220 - (25 \times 0.4) = 220 - 10 = 210 V$ .
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47.
Where DC compound motors are used?
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Answer: B —
Constant speed under varying load requirements
Cumulative compound motors are often used where constant speed under varying load is required.
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48.
How no-volt coil is connected in a 3- point starter with dc shunt motor?
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Answer: C —
Series with the shunt field
In a 3-point starter, the no-volt coil is connected in series with the shunt field winding.
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49.
What is the use of resistor connected with holding coil in 4-point starter?
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Answer: C —
Limit the current in the no-volt coil
The resistor in series with the holding coil (no-volt coil) in a 4-point starter limits the current to prevent overheating.
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50.
The most widely used speed control method is
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Answer: D —
Shunt field control
Shunt field control is the most common and efficient method for speed control above the rated speed.
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51.
Starting winding of a Single phase AC motor is :
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Answer: A —
High resistance and Low reactance
The starting winding is designed with high resistance to create a phase difference for starting torque.
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52.
Which statement is true in case of 3 phase squirrel cage induction motor : (i) Nearly constant speed (ii) Speed can vary by changing number of poles (iii) Maintenance high (iv) High starting torque
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Answer: B —
(i) and (ii) only
Squirrel cage motors have nearly constant speed and speed can be changed by pole changing; they are known for low maintenance.
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53.
The input power of an induction motor is 32 kW. The stator losses are 1 kW and friction and windage losses are 1.5 kW. What is the Rotor input?
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Answer: D —
31 kW
Rotor input = Input power - Stator losses = 32 kW - 1 kW = 31 kW.
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54.
Centrifugal switch of AC single phase motor is connected in :
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Answer: C —
Series with starting winding
The centrifugal switch is connected in series with the starting winding to disconnect it once the motor reaches speed.
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55.
What are the function of starter in 3 phase induction motor? (i) Limit inrush current (ii) Protect the motor from over load (iii) Protect from single phasing (iv) To start and stop motor
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Answer: C —
All of these
Starters for 3-phase induction motors perform all these functions including current limiting, overload protection, and control.
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56.
The method using for rapid stopping of an AC 3 phase induction motor by interchanging two stator lead is called :
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Answer: A —
Plugging
Plugging is a method of braking where two phases are interchanged to reverse the torque.
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57.
A slip ring induction motor runs at a synchronous speed of 375 RPM designed to operate on the Indian standard power frequency determine the number of poles ?
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Answer: D —
16 Poles
$N_s = \frac{120f}{P} \implies 375 = \frac{120 \times 50}{P} \implies P = \frac{6000}{375} = 16$ .
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58.
The working of a single phase AC motor based on :
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Answer: C —
Double revolving theory
The double revolving field theory explains the operation of single-phase induction motors.
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59.
The selection of a Starter in a 3 phase induction motor depends on : (i) Starting current (ii) Voltage rating of motor (iii) Types of load (iv) Slip of motor
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Answer: C —
(i), (ii) and (iii) only
Starter selection depends on starting current, voltage rating, and the nature of the load.
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60.
In a star-delta starter at starting the phase voltage is :
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Answer: B —
$\frac{1}{\sqrt{3}}$ times the line value
In star connection, phase voltage is $\frac{1}{\sqrt{3}}$ of the line voltage.
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61.
What thickness of laminations is usually used for a 50 Hz transformer operation?
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Answer: A —
0.25 to 0.27 mm
Laminations for 50 Hz transformers are typically thin (0.25-0.5 mm) to reduce eddy current losses.
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62.
What causes parallax error when reading an instrument?
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Answer: B —
Gap between the pointer and the scale
Parallax error occurs due to the gap between the pointer and the scale when viewed from an angle.
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63.
A multi-range meter is set to the 5V DC range. To measure a voltage, an operator uses the 0 – 50 scale and reads a value of 23.7. What is the actual measured voltage?
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Answer: C —
2.37 V
The scale factor is $5/50 = 0.1$ . So, $23.7 \times 0.1 = 2.37 \text{ V}$ .
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64.
Why does a Tangent Galvanometer require no prior calibration or comparison with other instruments?
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Answer: D —
It gives output directly in terms of deflection and instrument constants
A tangent galvanometer is an absolute instrument where the current is calculated using the tangent law and its physical constants.
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65.
What occurs if an AC voltage supply is connected to a standard DC PMMC voltmeter?
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Answer: C —
Pointer shows the RMS value
A PMMC instrument responds to the average value of current. For AC, the average is zero, causing the pointer to oscillate around zero.
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66.
What specific transformer core loss is reduced by adding silicon to the iron?
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Answer: A —
Hysteresis loss
Adding silicon to iron increases the resistivity of the material and reduces the hysteresis loop area, thereby reducing hysteresis loss.
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67.
What is the composition of steel and silicon steel in transformer core?
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Answer: B —
Iron 93% and silicon 7%
Silicon steel used in transformer cores typically contains about 3% to 4% silicon.
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68.
Under what condition does a transformer operate at maximum efficiency?
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Answer: D —
Core loss = Copperloss
Maximum efficiency in a transformer occurs when the variable copper loss equals the constant core (iron) loss.
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69.
How is heat dissipated from the transformer core and windings into the atmosphere in an oil-filled transformer?
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Answer: B —
Insulating oil transfers heat to cooling pipes
In oil-filled transformers, the oil acts as a coolant, circulating by convection to transfer heat from the core and windings to the tank walls or cooling pipes.
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70.
What is an isolation transformer?
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Answer: C —
A transformer where secondary voltage equals primary source voltage
An isolation transformer has a 1:1 turns ratio, providing electrical isolation between the primary and secondary circuits.
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71.
___________ is the luminous flux emitted by the light source per unit solid angle.
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Answer: D —
Luminous intensity
Luminous intensity is defined as the luminous flux per unit solid angle, measured in candela.
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72.
What is the condition for glowing LED?
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Answer: A —
Forward bias
An LED emits light when it is forward-biased, allowing charge carriers to recombine and release energy as photons.
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73.
Consider the following statements :\nThe width of depletion layer of a PN junction depends on ___________\n(i) The doping concentration of the P type semiconductor\n(ii) The doping concentration of the N type semiconductor\n(iii) The applied voltage across the junction\n(iv) Physical size or cross sectional area
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Answer: C —
Only (i), (ii) and (iii)
The depletion layer width depends on doping levels and the applied bias voltage, but is independent of the cross-sectional area.
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74.
Ripple factor of a full wave rectifier without filter will be :
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Answer: B —
0.482
The theoretical ripple factor for a full-wave rectifier is approximately 0.482.
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75.
Silicon is preffered for manufacturing zener diodes because :
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Answer: C —
Has high temperature and current capacity
Silicon is preferred over germanium for Zener diodes due to its higher temperature stability and current handling capability.
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76.
According to the inverse square law of illumination, how does the illuminance (E) on a surface change with respect to the distance (d) from a point source of light
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Answer: D —
E inversely proportional to $d^2$
The inverse square law states that $E = \frac{I}{d^2}$ , meaning illuminance is inversely proportional to the square of the distance.
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77.
Consider the following statements :\nThe emitter of a transistor is generally doped the heaviest because it ___________\n(i) has to dissipate maximum power\n(ii) has to supply the charge carriers\n(iii) is the first region of transistor
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Answer: B —
Only (ii)
The emitter is heavily doped to provide a large number of charge carriers for injection into the base.
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78.
The following are the donor impurities for silicon :
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Answer: D —
Phosphorus, Arsenic, Antimony
Donor impurities are pentavalent elements like Phosphorus, Arsenic, and Antimony.
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79.
The inner surface of the flourescent tube is coated with ––––––––––
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Answer: A —
Phosphor
Fluorescent tubes are coated with phosphor powder, which converts ultraviolet radiation into visible light.
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80.
–––––––––– device is used in automatic electric iron to regulate the temperature.
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Answer: B —
Thermostat
A thermostat is a temperature-sensitive switch used to maintain a constant temperature in appliances like electric irons.
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81.
Energy generated by using wind, tides, solar and biomass is known as\n(i) Conventional energy\n(ii) Non-conventional energy\n(iii) Non renewable energy
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Answer: C —
Only (ii)
Wind, solar, and biomass are renewable and classified as non-conventional energy sources.
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82.
Which is the main constituent of bio-gas?
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Answer: D —
Methane
Methane is the primary component of biogas, typically making up 50-75% of the gas.
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83.
Which of the following is not a constituent of hydro electric power station?
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Answer: C —
Boiler
A boiler is used in thermal power plants, not in hydroelectric power stations.
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84.
Which of the following statement/s is/are correct regarding nuclear power station?\n(i) A generating station which converts the nuclear energy into the electric energy\n(ii) It is a non conventional source of energy\n(iii) The atomic materials utilized for nuclear fission are thorium and uranium.
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Answer: B —
Only (i) & (iii)
Nuclear power is generally considered a conventional source of energy, while statements (i) and (iii) are correct.
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85.
A solar module is made up of large number of
Show answer and explanation
Answer: B —
Solar cells
A solar module consists of a series or parallel connection of multiple solar cells.
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86.
Which of the following component is not used in a thermal power plant?
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Answer: B —
Penstock
A penstock is a component of a hydroelectric power plant used to carry water to the turbine.
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87.
Which of the following statement/s is/are correct regarding Reaction turbines? (i) It is used for high heads (ii) It is used for low and medium heads (iii) Kaplan turbine is a reaction turbine
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Answer: C —
Only (ii) & (iii)
Reaction turbines are typically used for low to medium heads, and the Kaplan turbine is a well-known type of reaction turbine.
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88.
Match the components of a tidal Power plant with their functions. (a) Barrage (1) Controls the flow of water (b) Turbine (2) Prevents unwanted water flow through dam (c) Sluice (3) Converts water energy into mechanical energy (d) Embankment (4) Traps tidal water
Show answer and explanation
Answer: B —
(a)-(4), (b)-(3), (c)-(1), (d)-(2)
Barrage traps tidal water, turbine converts energy, sluice controls flow, and embankment prevents unwanted flow.
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89.
Which of the following is a penstock protection device used in hydro electric power plant?
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Answer: C —
Surge tank
A surge tank is used to protect the penstock from water hammer pressure surges.
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90.
Match the following based on wind Power plant : (a) Rotor blades (1) Provides excitation to generator (b) Exciter (2) Senses wind speed (c) Turbine controller (3) Convert wind energy into mechanical energy (d) Generator (4) Produces electrical energy
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Answer: A —
(a)-(3), (b)-(1), (c)-(2), (d)-(4)
Rotor blades convert wind energy to mechanical, exciter provides excitation, controller senses speed, and generator produces electricity.
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91.
Which of the following is/are the main components of an electrical power supply system? (i) The power station / Plant (ii) The transmission lines (iii) The distribution systems
Show answer and explanation
Answer: D —
All of the above (i), (ii) & (iii)
An electrical power supply system consists of generation, transmission, and distribution.
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92.
Match the stages of the power supply system with their corresponding voltage levels : Stage Voltage P Primary Transmission (i) 11 kV Q Primary Distribution (ii) 132 kV / 220 kV / 400 kV R Secondary Distribution (iii) 415 V Select the correct matching :
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Answer: A —
P-(ii), Q-(i), R-(iii)
Primary transmission uses high voltages (132kV+), primary distribution uses 11kV, and secondary distribution uses 415V.
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93.
Which AC system is universally adopted for power transmission as an economical proposition?
Show answer and explanation
Answer: C —
Three-phase three-wire AC system
Three-phase three-wire systems are the most economical for long-distance power transmission.
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94.
The current in a feeder is :
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Answer: B —
Constant in each point
In a feeder, current varies along its length because loads are tapped off at various points.
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95.
Consider the following statements regarding DC transmission : Statement I : DC transmission requires only two conductors. Statement II : DC transmission has no skin effect on conductors. Choose the correct answer.
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Answer: A —
Both Statement I and Statement II are true
DC transmission uses two conductors and does not exhibit skin effect, which is a phenomenon specific to AC.
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96.
Consider the following statements : Statement I : Step-up and step-down transformation of DC voltage is possible in equipment like transformer. Statement II : AC voltages can be conveniently stepped up or stepped down using transformers. Choose the correct answer.
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Answer: C —
Statement I is false, but Statement II is true
Transformers operate on the principle of electromagnetic induction, which requires changing magnetic flux, thus they only work with AC.
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97.
Which of the following is NOT an advantage of DC transmission?
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Answer: C —
It can’t be stepped up or stepped down using transformers
The inability to use transformers for voltage level changes is a disadvantage of DC transmission, not an advantage.
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98.
Consider the following statements : (i) Effective resistance of AC transmission lines is increased due to skin effect. (ii) For the same value of voltage, insulating material on DC lines experience less stress as compared to those on AC transmission lines. (iii) AC transmission has no problem of inductance and capacitance. Which of the above statements are correct?
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Answer: A —
Only (i) & (ii)
Skin effect increases effective resistance in AC. DC insulation stress is lower. AC transmission is significantly affected by inductance and capacitance.
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99.
Which transmission system has lower voltage drop for the same load and sending-end voltage?
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Answer: B —
DC transmission
DC transmission has lower voltage drop because it lacks inductive reactance and skin effect.
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100.
At the receiving end of an HVDC system, DC is converted into AC using a/an :
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Answer: A —
Inverter
An inverter is used to convert DC to AC at the receiving end of an HVDC link.
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Final answer keyEnglishSame post
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Clerk, Amenities Assistant,Sales Assistant,Worker/Plant Attender Grade III etc- Various Dept
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More papers to practise

Divisional Accounts Officer (Cat. No. 192/2024)Paper IV - Kerala State Electricity Board Ltd

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Clerk, Amenities Assistant,Sales Assistant,Worker/Plant Attender Grade III etc- Various Dept