1. A battery has an emf of 12.9 volts and supplies a current of 3.5 A. What is the resistance of the circuit?

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1 1. A battery has an emf of 12.9 volts and supplies a current of 3.5 A. What is the resistance of the circuit? (a) 3.5 Ω (b) 16.4 Ω (c) 3.69 Ω (d) Ω 2. Sign convention used for potential is: (a) Rise in potential is negative (b) rise in potential is zero (c) rise in potential is equal to fall in potential (d) rise in potential is positive 3. If the above circuit 3, the potential of E 2 is (a) 0V (b) 4V (c) 2V (d) 1V Figure 3 4. Four cells, each of emf 1.5v and internal resistance 0.5 Ω are connected in parallel across an external resistance of 2.5Ω. What is the current supplied by each cell? (a) (b) 2 (c) (d) The main factors which determine the inductive reactance are (a) inductance and applied emf (b) frequency and current (c) inductance and frequency (d) frequency and induced emf 6. One sine wave has a positive peak at 75 0, another has a positive peak at How much in each sine wave shifted in phase from 0 0 reference. (a) 15 0, 15 0 (b) 10 0, 10 0 (c) (d) 15 0, Find the maximum value of the alternating current I = 4.2 sin (5000t )A (a) 4.02 A (b) 4.2 A (c) 2.97 A (d) 0.42 A 8. For series RC circuit, the relation between voltage and current is (a) voltage leads the current by φ (b) voltage lags the current by φ (c) voltage leads by φ (d) voltage is equal to currents 9. In the circuit 9 shown, Power consumed by 2Ω resistor is (a) W (b) 1.512W (c) (d) In a balanced Delta connection, I P h = (a) I L / 3 (b) I L (c) 2I L (d) 3I L Figure The armature of a 8-pole d.c generator has 960 conductors and runs at 400rpm. The flux per pole is 40m Wb. Calculate the induced emf if the armature is lap wound? (a) 250V (b) 256V (c) 300V (d) 200V 12. A 4 pole shunt generator with lap-connected armature supplies a load of 200 A at 100 V. Shunt field resistance is 50 ohms, and armature resistance is 0.05 ohm. Calculate the total armature current (a) 20 A (b) 202 A (c) 2020 A (d) 200 A 13. If a DC motor is to be selected for conveyors, which motor would be preferred? (a) Shunt motor (b) Cumulative compound motor. (c) Differentially compound motor (d) Series motor 14. A 230V dc shunt motor has an armature resistance of 0.3 Ω. Calculate the resistance to be connected in series with the armature to limit the armature current to 75 A at starting (a) 0 Ω (b) Ω (c) Ω (d) 2 Ω 15. A 1000/200V transformer takes 0.3 A at p.f of 0.2 on open circuit. Find the magnetizing, and iron loss component of no-load primary current (a) 0.3A, 0.6A (b) 0.294A, 0.06A (c) 0.4A, 0.8A (d) 0.294A, 0.6A 16. The frequency of voltage generated by an alternator having 4 poles and rotating at 1800rpm is hertz. (a) 40 (b) 20 (c) 60 (d) A 3-phase, 4-pole, 50Hz. Induction motor runs at 1440rpm determine the percentage slip of the induction motor. (a) 8% (b) 5% (c) 2% (d) 4% 18. The moving coil of a meter has 50 turns and width of 2cm and depth of 3m. it is placed in a uniform radial field of 5o, wb/m 2. Find the turning moment of coil when it is carrying, 1mA current. (a) Nm (b) Nm (c) Nm (d) 1.5Nm 19. An ammeter is used to measure the flow of in a circuit (a) Voltage (b) Current (c) Power (d) Energy 20. Slow, but continuous rotation of the disc of an energy meter is called (a) creeping (b) sweeping (c) crawling (d) friction error

2 1. A battery has an emf of 12.9 volts and supplies a current of 3.5 A. What is the resistance of the circuit? (a) 3.69 Ω (b) 16.4 Ω (c) 3.5 Ω (d) Ω 2. What is the current in the circuit 2 shown below? (a) 2mA (b) 2A (c) 0.2A (d) 2µA Figure 2 3. If one of the resistors in parallel circuit is removed, what happens to the total resistance (a) remain constant (b) exactly doubles (c) increases (d) decreases 4. A battery has 3 cells in parallel. Each has an emf of 1.5V and internal resistance 0.6Ω. Find the current delivered by it into a load of 1.8Ω (a) 1A (b) 75A (c) 7.5A (d) 0.75A 5. A pure inductive coil allows a current of 10 A to flow from a 230v, 50Hz supply. What is the Inductance of the coil? (a) 23.5/ ΠΩ (b) 0.23/ΠΩ (c) 10/ ΠΩ (d) 26/ ΠΩ 6. Average of 230V, 50Hz is applied to a 318 µ F pure capacitor, what is the equation for current? (a) sin (314t - Π/2) (b) 23 sin (314t + Π/2) (c) 23 sin 314t (d) sin (314t + Π/2) 7. A coil having a resistance of 15 Ω and an inductance of 0.1H is connected in series with a 230 V, 50Hz supply. Calculate the phase difference between voltage and current (a) 64 0 (b) 90 0 (c) (d) A capacitor of capacitance 79.5 µf is connected in series with a non inductive resistance of 30Ω across 100v, 50Hz supply. Find the capacitive reactance of the circuit (a) 42Ω (b) 38Ω (c) 40Ω (d) 47Ω 9. A coil of resistance 100 Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the current through the circuit at resonance. (a) 1A (b) 0.1A (c) 0.01A (d) 10A 10. In a 3-phase delta connected balanced system, the phase difference of voltages is (a) 24 0 (b) 0 0 (c) 60 0 (d) A d.c series motor should always be started with load, because it at no-load (a) cannot start (b) will rotate at dangerously high speed (c) will not develop high starting torque (d) draws a small current 12. If a shunt generator fails to buildup any voltage at no-load, the reason may be that (a) Load resistance is more than critical resistance (b) There is excess of residual Magnetism. (c) Field resistance is less than critical resistance (d) There is no residual Magnetism 13. Which DC motor is generally preferred for cranes and hoists? (a) Cumulative compound motor (b) Differentially compound motor (c) Shunt motor (d) Series motor 14. An ideal transformer does not change (a) power factor (b) voltage (c) current (d) power 15. Eddy current loss in a transformer depends on (a) voltage alone (b) current alone (c) frequency alone (d) both current and frequency 16. A salient pole synchronous motor is running at no-load if its field current is switched off, then the motor will (a) remain running at synchronous speed (b) remain running at a speed slightly more than the synchronous (c) remain running at a speed slightly less than the synchronous speed (d) come to stop 17. Single phase induction motor are made self starting by (a) using an external starting device (b) increasing rotor resistance (c) decreasing rotor resistance (d) providing an additional winding on the stator called the auxiliary winding 18. The damping torque provided in moving coil instruments is (a) Mechanical (b) Fluid Friction Damping (c) Eddy current (d) Air friction 19. The force responsible for reduction of oscillations in an ammeter is (a) controlling force (b) damping force (c) deflecting and controlling force (d) deflecting force 20. Slow, but continuous rotation of the disc of an energy meter is called (a) friction error (b) crawling (c) creeping (d) sweeping

3 1. In the Figure 1 the current direction is Figure 1 (a) from b to a (b) only b (c) from a to b (d) only a 2. In any closed circuit, the algebraic sum of all the electromotive forces and the voltage drops is equal to (a) two (b) zero (c) constant (d) one 3. For a parallel circuit, which statement is correct (a) I 1 + I 2 + I 3 = 0 (b) P T = P 1 + P 2 + P m (c) I i = RT R i +R T I T (d) P T = V S2 R T 4. Ten cells, each of emf 1.5v and Internal resistance 0.2Ω are connected in series. What current will they send through an external resistance of 4Ω (a) 6.0 (b) 60 (c) 2.5 (d) In a pure resistive circuit, the instantaneous voltage and current are given by V=250sin 314t; i=10sin 314t. What is the peak power consumed in the circuit? (a) 2500W (b) 1000W (c) 2000W (d) 1200W 6. In the figure 6 shown, below the wave form belongs to (a) pure resistor (b) pure capacitor (c) Inductor (d) pure Inductor Figure 6 7. The equation of 50 Hz ac sinusoidal current having an rms value of 10A is (a) 10 sin (2Π 50 t) (b) [2Π 50 (t φ)] (c) 14.4 sin (2Π 50 t) (d) 10[2Π 50 (t + φ)] 8. A coil of 0.06H and 2.5 Ω is connected in series with a 6.8 µf capacitor is connected to a 230V, 50Hz a c supply. Calculate the effective reactance of the circuit (a) Ω (b) 510.3Ω (c) 620.9Ω (d) A coil of resistance 100Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the Q factor of the circuit (a) 10 (b) 1 (c) 0.1 (d) If the instantaneous values of phases R and Y in a 3 - φ circuit are +60V and 40v respectively then phase B must be (a) -100V (b) 80V (c) -20V (d) 100V 11. A d.c series motor should always be started with load, because it at no-load (a) will not develop high starting torque (b) will rotate at dangerously high speed (c) cannot start (d) draws a small current 12. A 100KW 240V shunt generator has a field resistance of 55Ω and armature resistance of 0.067Ω. Find the full load generated voltage (a) (b) 240 (c) 256 (d) DC shunt motors should never be started on heavy loads because (a) loads need zero starting torque (b) loads need no starting torque (c) loads need minimum starting torque (d) loads need heavy starting torque 14. A 230V dc shunt motor has an armature resistance of 0.3 Ω. Calculate the resistance to be connected in series with the armature to limit the armature current to 75 A at starting (a) 0 Ω (b) 2 Ω (c) Ω (d) Ω 15. No load test on a transformer is carried out to determine (a) Copper loss (b) Efficiency of the transformer. (c) Magnetising current and loss (d) Magnetising current 16. The frequency of voltage generated by an alternator having 4 poles and rotating at 1800rpm is hertz. (a) 60 (b) 40 (c) 80 (d) For which Induction motor the speed can be controlled from rotor side? (a) Shunt Motor (b) Squirrel case and slip ring (c) Squirrel case (d) Slip ring 18. In a moving iron instrument, controlling torque is proportional to (a) current (b) deflection (c) torque (d) voltage 19. An ammeter is connected with the load (a) In parallel (b) Across the load (c) In shunt (d) In Series 20. Watt hour meter is used to measure (a) Energy (b) Voltage (c) Power (d) Current

4 1. In the above circuit 1, the current coming to node A from 2 Ω resistor is Figure 1 (a) 2A (b) 10A (c) 1A (d) 4A 2. In a series circuit, which of the statement is correct (a) total power = sum of powers of each resistor in series (b) total power = V I cos φ (c) total power = infinity (d) total power = zero 3. For the circuit 3 shown below, find the total resistance. (a) 150 Ω (b) 100 Ω (c) 250Ω (d) 200 Ω 4. Define frequency (a) the number of cycles that occur in 2 seconds (b) the number of cycles that occur in 4 seconds (c) the number of cycles that occur in 1 second (d) the number of cycles that occur in half seconds Figure 3 5. A pure inductive coil allows a current of 10A to flow from a 230v, 50Hz supply. Write down the equation for current (a) sin (314t - Π/2) (b) 10 sin (314t - Π/2 ) (c) sin (314t + Π/2) (d) 10 sin 314t 6. In a pure capacitance, the phasor eldation between V and I is (a) I lags V by Π/2 (b) I and V are opposite (c) I and V are in phase (d) I leads V by Π/2 7. Average value of a sinusoidal alternating quantity should be computed over one half - cycle only because the (a) average value over a complete cycle is less accurate (b) average value over one half-cycle is more accurate (c) average value is always less than the maximum value (d) average value over a complete cycle is zero 8. In an RLC circuit, phase angle is given by (a) tan [ 1 X L X c ] R (b) sin [ 1 X L X c ] R (c) cos [ 1 X L X c ] R (d) zero 9. Series resonant frequency is given by (a) 1 2Π LC (b) X L (c) X L - X C (d) X C 10. In a balanced Delta connection, total 3φ power in terms of phase quantities is (a) V P h I P H cos φ (b) V P h I P H (c) 3V P h I P H cos φ (d) 3V P h I P H cos φ 11. The part which converts alternating voltage to a direct voltage in a DC machine is (a) Commutator (b) Armature (c) Poles (d) Brushes 12. A 4 pole shunt generator with lap-connected armature supplies a load of 200 A at 100 V. Shunt field resistance is 50 ohms, and armature resistance is 0.05 ohm. Calculate the total armature current (a) 200 A (b) 202 A (c) 2020 A (d) 20 A 13. What type of motors are used to get large starting torque (a) blower (b) fans (c) electric railways (d) conveyors 14. A 230V dc shunt motor has an armature resistance of 0.3 Ω. Calculate the resistance to be connected in series with the armature to limit the armature current to 75 A at starting (a) 2 Ω (b) Ω (c) Ω (d) 0 Ω 15. Maximum efficiency occurs when (a) copper loss = iron loss (b) copper loss = zero (c) copper loss + iron loss = zero (d) iron loss = zero 16. Emf equation of an alternator. (b) 4.44φfz (c) 4.44K c.k d φft (d) 4.44fz 17. When the torque is zero, slip is (a) 5 (b) 100 (c) 1 (d) The moving coil of a meter has 50 turns and width of 2cm and depth of 3m. it is placed in a uniform radial field of 5o, wb/m 2. Find the turning moment of coil when it is carrying, 1mA current. (a) Nm (b) Nm (c) 1.5Nm (d) Nm 19. A 0-300V voltmeter has an error of +2% of full scale deflection. What would be the range if readings of true voltage is 30V (a) V (b) 10-20V (c) 24-30V (d) 20-40V 20. Define meter constant (a) No. of revolutions made per Newton (b) No. of revolutions made per kilo-watt hour (c) No. of revolutions made per hour. (d) No. of revolutions made per watt

5 1. State Kirchoff s current Law. (a) sum of all powers in a circuit (b) sum of all positive currents is equal to sum of all negative currents. (c) sum of all positive emfs is equal to the sum of all negative emfs taken in order (d) sum of all emfs in a circuit 2. In any closed circuit, the algebraic sum of all the electromotive forces and the voltage drops is equal to (b) two (c) constant (d) one 3. For a parallel circuit, which statement is correct (a) P T = V S2 R T (b) I 1 + I 2 + I 3 = 0 (c) P T = P 1 + P 2 + P m (d) I i = RT R i +R T I T 4. One cycle of corresponds to (a) 4 Π radians (b) 2Π radians (c) 0 radians (d) Π radians 5. The main factors which determine the inductive reactance are (a) inductance and frequency (b) frequency and induced emf (c) frequency and current (d) inductance and applied emf 6. The reactance of a capacitor at 50 Hz is 5 Ω. If the frequency is increased to 100 Hz, the new reactance is (a) 2.5 Ω (b) 10 Ω (c) 125Ω (d) 5Ω 7. For series R L circuit, impedance is given by (a) z = R 2 + L 2 (b) z = R 2 (c) z = R 2 + X 2 1 (d) z = XL 2 8. A coil of 0.06H and 2.5 Ω is connected in series with a 6.8 µf capacitor is connected to a 230v, 50Hz a c supply. Calculate the effective impedance of the circuit (a) 510.3Ω (b) Ω (c) 620.9Ω (d) 470.2Ω 9. In an RC circuit, true power is 300W and reactive power is 1000W. What is the apparent power? (a) 1000VAR (b) 1000W (c) 1000VA (d) VA 10. Calculate the line currents in a balanced delta connected load taking 75 KW at a power factor 0.8 from a 3-phase, 440V supply. (a) 150A (b) 125A (c) 123A (d) 100A 11. A six pole lap connected generator has a useful flux/pole of 0.045wb. If the no load voltage at 400rpm is 300V, find the conductors on the Armature periphery. (a) 400 (b) 1000 (c) 1800 (d) A compound generator is to supply a load of 250 lamps, each rated at 100W, 250V. The armature, series and shunt field resistances are 0.06, 0.04 and 50Ω respectively. What is the value of armature current when connected in short shunt. (a) 100A (b) 105A (c) A (d) A 13. Which DC motor will be preferred for constant speed line shafting? (a) Cumulative compound motor (b) Differentially compound motor. (c) Shunt motor (d) Series motor 14. While controlling the speed of a dc shunt motor, what should be done to achieve a constant torque drive? (a) applied power should be kept constant (b) applied voltage should be maintained constant (c) applied torque is zero (d) applied current should be kept constant 15. A 1000/200V transformer takes 0.3 A at p.f of 0.2 on open circuit. Find the magnetizing, and iron loss component of no-load primary current (a) 0.4A, 0.8A (b) 0.294A, 0.6A (c) 0.294A, 0.06A (d) 0.3A, 0.6A 16. A 50 Hz alternator will run at the greatest possible speed if it is wound for poles (a) 6 (b) 2 (c) 4 (d) A 3-phase, 4-pole, 50Hz. Induction motor runs at 1440rpm determine the percentage slip of the induction motor. (a) 5% (b) 4% (c) 2% (d) 8% 18. The shape of the coil used in permanent magnet moving coil instruments is (a) Rectangular (b) Parabola (c) Circular (d) Elliptical 19. An ammeter is a instrument (a) recording (b) absolute (c) secondary (d) integrating 20. In Dynamometer type wattmeter, fixed coils are connected in with the load (a) series (b) shunt (c) parallel (d) zero

6 1. In the circuit 1 shown below, find the total current Figure 1 (a) I 1 +I 2 + I 3 = I 4 +I 5 (b) I 1 +I 3 = I 2 +I 4 +I 5 (c) zero (d) I 1 +I 2 + I 3 +I 4 +I 5 = 0 2. Droop across y Ω shown in figure 2 is Figure 2 (a) 66.66V (b) 6.66V (c) 0.066V (d) 0.66V 3. In the circuit 3 shown below. What is the resistance across ac (a) 1 Ω (b) 8 Ω (c) 10Ω (d) 9Ω Figure 3 4. A battery of emf 1.8 volts and internal resistance 1.2Ω is connected to a pair of resistance 4Ω and 6Ωin parallel. Calculate the potential difference of the battery (a) 100V (b) 1V (c) 1.2V (d) 10V 5. The A.C voltage across a 150Ω resistor is 39 sin (2Πtimes10 3 t)v At what value of t does the current through the resistor equal to -0.26A? (a) 1.0 m sec (b) 0.75 m sec (c) 10 m sec (d) 7.5 m sec 6. Figure 6 shown below The peak to peak value of (a) 12V (b) 0V (c) -6V (d) +6V 7. For series R L circuit, impedance is given by (a) z = R 2 (b) z = R 2 + L 2 (c) z = XL 2 (d) z = R 2 + X 2 1 Figure 6 8. A capacitor and resistor are connected in series across a 120V, 50Hz supply. A circuit draws a current of 1.144A. If power loss in the circuit is W, find the value of capacitance (a) 50 µ F (b) 200 µ F (c) 100 µ F (d) 10 m F 9. Given V(t) = 100 sin (50t ) true power is 200W, power factor is lagging. What are the elements present? (a) RL (b) LC (c) RC (d) R 10. What is the power in a delta connected system? (a) V L I L cos φ (b) unity (c) 3V L I L cos φ (d) Why does saturation curve starts from some value higher than zero? (a) due to power loss (b) due to eddy current loss (c) due to residual magnetism (d) due to hysterisis loss 12. In a shunt generator Ish = (a) V+I a R a (b) V/R sh (c) V-I a R sh (d) V R sh 13. The condition for maximum power in case of DC motor is (a) Supply voltage = back emf (b) Supply voltage = 1 / 2 back emf (c) back emf = 2 supply voltage (d) back emf = 1 / 2 supply voltage 14. The principle of operation of transformer is (a) law of electromagnetic induction (b) Lenz s law (c) law of conservation of mass (d) law of conservation of energy 15. Which of the following is not a part of transformer installation? (a) Conservator (b) Iron core (c) Breather (d) Exciter 16. A 4-pole, 1200 rpm alternator generates emf at a frequency of (a) 25Hz (b) 50Hz (c) 40Hz (d) 60Hz 17. When the torque is zero, slip is (a) 1 (b) 100 (c) 10 (d) The shape of the coil used in permanent magnet moving coil instruments is (a) Rectangular (b) Elliptical (c) Parabola (d) Circular 19. Ammeter is an instrument which measures (a) power (b) distance (c) voltage (d) current 20. Define meter constant (a) No. of revolutions made per kilo-watt hour (b) No. of revolutions made per watt (c) No. of revolutions made per hour. (d) No. of revolutions made per Newton

7 1. State Kirchoff s current Law. (a) sum of all powers in a circuit (b) sum of all emfs in a circuit (c) sum of all positive currents is equal to sum of all negative currents. (d) sum of all positive emfs is equal to the sum of all negative emfs taken in order 2. In a series circuit, which of the statement is correct (a) total power = sum of powers of each resistor in series (b) total power = V I cos φ (c) total power = zero (d) total power = infinity 3. In a parallel circuit, the relation between different currents is (a) Zero = I 1 + I 2 + I 3 + I 4 + (b) I 1 + I 2 + I 3 + = infinity (c) I T = I 1 I 2 I 3 (d) I T = I 1 + I 2 + I An alternating current I is given by I = sin 314t. What is the time period of the wave form of i? (a) 0.02 (b) (c) (d) A pure inductive coil allows a current of 10A to flow from a 230v, 50Hz supply. Write down the equation for current (a) sin (314t - Π/2) (b) 10 sin (314t - Π/2 ) (c) 10 sin 314t (d) sin (314t + Π/2) 6. In the figure 6 shown below the wave form belongs to (a) pure capacitor (b) pure resistor (c) pure inductor (d) Inductor 7. Form Factor of an alternating Quantity is define as (a) RMS value/average value (b) average value/rms value (c) RMS value/peak value (d) average value/peek value Figure 6 8. A coil of 0.06H and 2.5 Ω is connected in series with a 6.8 µf capacitor. What is the power factor of the circuit (a) 0.6 (b) 0.8 (c) (d) Average power for a reactive circuit is (a) 0 (b) -1 (c) infinity (d) Voltage V RY = , what does V Y R equal? (a) (b) (c) (d) A lap wound dc machine has 400 conductors and 8 poles the voltage induced per conductor is 2v. The machine generates a voltage of (a) 400 V (b) 100 V (c) 200 V (d) 800 V 12. A 4 pole shunt generator with lap-connected armature supplies a load of 200 A at 100 V. Shunt field resistance is 50 ohms, and armature resistance is 0.05 ohm. Calculate the total armature current (a) 200 A (b) 20 A (c) 202 A (d) 2020 A 13. If T a be the torque and I a the armature current for a DC motor, then which of the following relation is valid before saturation. (a) Ta α I/I a (b) Ta α I/(Ia) 2 (c) Ta α Ia 2 (d) Ta α Ia 14. A 50 KVA, single phase transformer has 600 turns on primary and 40 turns on secondary. The primary winding is connected to 2.2 KV, 50Hz supply. Determine secondary voltage at no load (a) V (b) 100V (c) 150V (d) 200V 15. A 1000/200V transformer takes 0.3 A at p.f of 0.2 on open circuit. Find the magnetizing, and iron loss component of no-load primary current (a) 0.3A, 0.6A (b) 0.294A, 0.6A (c) 0.294A, 0.06A (d) 0.4A, 0.8A 16. The speed of a 4 pole, 60Hz synchronous machine will be (a) 3000rpm (b) 2400rpm (c) 1800rpm (d) 3600rpm 17. A 3-phase, 4-pole, 50Hz. Induction motor runs at 1440rpm determine the percentage slip of the induction motor. (a) 8% (b) 5% (c) 2% (d) 4% 18. In a moving iron instrument, controlling torque is proportional to (a) torque (b) current (c) voltage (d) deflection 19. A moving coil instrument has a resistance of 0.6Ω and a full scale deflection of 0.1A. to convert it into an ammeter of 0-15A range, the resistance of the shunt should be (a) 0.1Ω (b) 0.004Ω (c) 00.6Ω (d) 0.6Ω 20. In Dynamometer type wattmeter fixed coil is called (a) Potential coil (b) Power coil (c) Energy coil (d) Current coil

8 1. The ratio of potential difference (v) between the ends of a conductor to the ohms law current ( I ) flowing between them is (a) 2 (b) Π (c) constant (d) one 2. Find the voltage between A and B, for the figure 2 shown below (a) 10V (b) 90V (c) 100V (d) 900V Figure 2 3. In a parallel circuit, the relation between different currents is (a) I T = I 1 I 2 I 3 (b) I 1 + I 2 + I 3 + = infinity (c) I T = I 1 + I 2 + I 3 + (d) Zero = I 1 + I 2 + I 3 + I A battery of emf 1.8 volts and internal resistance 1.2Ω is connected to a pair of resistance 4Ω and 6Ωin parallel. Calculate the potential difference of the battery (a) 1V (b) 1.2V (c) 100V (d) 10V 5. The current in a 2.2 k Ωresistor is I = 5 sin (2 Π 100t ) ma. What is the effective value of resistor voltage? (a) 0.778V (b) 7.78V (c) 778.0V (d) 77.8V 6. A 230V, 50Hz supply is connected to a 50 µ F capacitor, what is the power consumed by the capacitor? (a) 2.8J (b) 2.645J (c) 3.2J (d) 0 J 7. Find the peak to peak value of an ac voltage whose effective value is 50V rms? (a) 7.07 V (b) V (c) zero (d) 70.7 V 8. A 10Ω resistor and 400 µf capacitor are connected in series to a 60 V sinusoidal supply. The circuit current is 5 A. What is the supply frequency (a) 55Hz (b) 60Hz (c) 65Hz (d) 50Hz 9. A coil of resistance 100 Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the current through the circuit at resonance. (a) 1A (b) 0.01A (c) 10A (d) 0.1A 10. A balanced delta connected load of (2+j3) ohms per phase is connected to a balanced 3-phase 440V supply. The phase current is 10A. Find active power. (a) 10KW (b) 50KW (c) 7.26KW (d) 100KW 11. A d.c series motor should always be started with load, because it at no-load (a) cannot start (b) will rotate at dangerously high speed (c) draws a small current (d) will not develop high starting torque 12. The factor that is not responsible for drop in terminal voltage of a dc shunt generator on load is (a) field weakening due to armature reaction and armature resistance drop (b) commutation (c) armature resistance drop (d) armature reaction 13. Which DC motor will be preferred for constant speed line shafting? (a) Series motor (b) Differentially compound motor. (c) Cumulative compound motor (d) Shunt motor 14. Torque and armature current characteristic is (a) parabolic (b) straight line (c) circle (d) hyper bolic 15. Material used for construction of transformer core is usually (a) Copper (b) Aluminum (c) Silicon steel (d) Wood 16. Under no load condition. Power drawn by the prime mover of an alternator of is to (a) Produce Power in the armature (b) produce induced emf in armature winding (c) Meet can losses both in armature and rotor windings (d) Meet no load losses 17. When the induction motor is stand still, the slip is (b) 1 (c) infinity (d) In moving iron instrument, torque is proportional to (a) first derivative of inductance with respect to deflection angle. (b) current (c) first derivative of inductance with respect to time (d) inductance of instrument 19. The multiplier and the meter coil in a voltmeter are in (a) series-parallel (b) series (c) parallel (d) shunt 20. Units of Energy are (a) Newton (b) meters/sec (c) Joule (d) Watts

9 1. In the Figure 1 the current direction is Figure 1 (a) only b (b) only a (c) from b to a (d) from a to b 2. Kirchoff s voltage law is written as (b) E=V 1 + V 2 (c) E+V 1 + V 2 =0 (d) V 1 + V 2 =0 3. In the figure 3 shown below find the current in the resistor R 1 (a) 16.6A (b) 15V (c) 15A (d) 16.6V Figure 3 4. What is the instantaneous value of V = 5sin (2Π 10 4 t) volts at time (t) = 25µ sec (a) 0V (b) 0.137V (c) 10V (d) -10V 5. A pure inductive coil allows a current of 10 A to flow from a 230v, 50Hz supply. What is the Inductance of the coil? (a) 23.5/ ΠΩ (b) 10/ ΠΩ (c) 26/ ΠΩ (d) 0.23/ΠΩ 6. The power wave form corresponding to a pure inductance contains no. of half cycles (a) 4 (b) 8 (c) 2 (d) 6 7. Find the peak to peak value of an ac voltage whose effective value is 50V rms? (b) 70.7 V (c) 7.07 V (d) V 8. A coil of 0.06H and 2.5 Ω is connected in series with a 6.8 µf capacitor is connected to a 230V, 50Hz a c supply. Calculate the effective reactance of the circuit (a) Ω (b) (c) 620.9Ω (d) 510.3Ω 9. Determine the average power delivered to the circuit consisting of an impedance Z=5+j8 when the current flowing through the circuit is I= (a) 625W (b) 235.8W (c) 100W (d) 10W 10. A balanced 3-phase load consists of three coils, each of resistance 5 Ωand capacitive reactance of 4Ω. Calculate magnitude of line current if a balanced 3-φ source of 100v is applied across it (a) 6.928A (b) 69.28A (c) 9.02A (d) zero 11. A d.c series motor should always be started with load, because it at no-load (a) will rotate at dangerously high speed (b) cannot start (c) will not develop high starting torque (d) draws a small current 12. A compound generator is to supply a load of 250 lamps, each rated at 100V, 250V. The armature, series, shunt field winding resistances are and 50Ω respectively. What is the value of generated emf when connected in long shunt? (a) (b) (c) 250V (d) If T a be the torque and I a the armature current for a DC motor, then which of the following relation is valid before saturation. (a) Ta α Ia (b) Ta α I/I a (c) Ta α I/(Ia) 2 (d) Ta α Ia While controlling the speed of a dc shunt motor, what should be done to achieve a constant torque drive? (a) applied power should be kept constant (b) applied torque is zero (c) applied current should be kept constant (d) applied voltage should be maintained constant 15. A transformer can have regulation closer to zero (a) On leading power factor (b) On over load (c) On full load (d) On zero Power factor 16. The speed of a P-pole synchronous machine in rpm is given by (a) 120f/P (b) 120 P/F (c) 120P/f (d) Root of 120f/P 17. After starting winding of a single phase induction motor is disconnected from supply, it continuous to run only on winding. (a) Running (b) Field (c) Rotor (d) Compensating 18. The shape of the iron piece used in Attraction type moving iron instruments is (a) Circular (b) Elliptical (c) Rectangular (d) Oval 19. An ammeter is a instrument (a) integrating (b) recording (c) absolute (d) secondary 20. Units of Energy are (a) Newton (b) Joule (c) Watts (d) meters/sec

10 1. A resistor takes 0.3 A at 230v. If the voltage is reduced to 100v, What is the current taken by the resistor (a) 0.13 A (b) 0.69 A (c) 0.18 A (d) 0.3 A 2. The following voltage drops are measured across each of three resistors in series: 5.2V, 8.5V, 12.3V. What is the value of the source voltage to which these resistors are connected? (a) 26V (b) 5.2V (c) 8.2V (d) 12.3V 3. Power in a parallel circuit is equal to (a) product of all powers (b) sum of all resistors in parallel (c) sum of all powers in parallel (d) product of all resistors in parallel 4. A cell of emf 2V and internal resistance 1Ω is connected with two wires of resistances 2Ω and 5Ω in parallel. Find the current through the circuit (a) 100/12A (b) 17/14A (c) 0 A (d) 14/17A 5. The main factors which determine the inductive reactance are (a) frequency and current (b) inductance and frequency (c) frequency and induced emf (d) inductance and applied emf 6. One sine wave has a positive peak at 75 0, another has a positive peak at How much in each sine wave shifted in phase from 0 0 reference. (a) 15 0, 10 0 (b) 15 0, 15 0 (c) 10 0, 10 0 (d) What is the effective value of sine wave with a maximum value of 95V? (b) 95V (c) 50V (d) 67.2V 8. In an RLC series circuit, if the difference between X L and X C increases, then the total (a) impedance remains unchanged (b) impedance increases (c) impedance reduce (d) resistance increases 9. For resonant series circuit, for f < fr, the behavior of circuit is (a) circuit is resistive (b) circuit is R - L - C (c) circuit is capacitive (d) circuit is inductive 10. In a balanced Delta connection, I P h = (a) I L / 3 (b) I L (c) 3I L (d) 2I L 11. Why is armature core of dc generator laminated? (a) to reduce friction and windage loss (b) to reduce hysteresis loss (c) to reduce eddy current loss (d) to reduce copper losses 12. In a shunt generator Ish = (a) V R sh (b) V-I a R sh (c) V+I a R a (d) V/R sh 13. DC shunt motors should never be started on heavy loads because (a) loads need heavy starting torque (b) loads need minimum starting torque (c) loads need no starting torque (d) loads need zero starting torque 14. The path of a magnetic flux in a transformer should have (a) High reluctance (b) Low reluctance (c) High resistance (d) Low resistance 15. The full load copper loss of a transformer is 1600W. At half load the copper loss will be (a) 1600W (b) 6400W (c) 800W (d) 400W 16. The frequency of voltage generated by an alternator having 4 poles and rotating at 1800rpm is hertz. (a) 80 (b) 20 (c) 60 (d) If N S is the synchronous speed and s is the slip, then the actual running speed of an induction motor will be (a) (1-s) N S (b) N S (c) s N S (d) (N S 1) s 18. In the attraction type moving Iron instruments the deflection is proportional to (a) Square of coil current (b) Square root of coil current (c) Cube of coil current (d) of coil current 19. A 0-300V voltmeter has an error of +2% of full scale deflection. What would be the range if readings of true voltage is 30V (a) 20-40V (b) 24-30V (c) 10-20V (d) V 20. Slow, but continuous rotation of the disc of an energy meter is called (a) creeping (b) sweeping (c) crawling (d) friction error

11 1. Graph between current and voltage if the resistance of the circuit is kept constant is (a) semi-circle (b) hyperbolic (c) straight line (d) parabolic 2. What is the rule followed for kirchoff s voltage law? (a) loop rule (b) mesh rule (c) wheat stone rule (d) current rule 3. Power in a parallel circuit is equal to (a) sum of all resistors in parallel (b) product of all powers (c) sum of all powers in parallel (d) product of all resistors in parallel 4. Ten cells, each of emf 1.5v and Internal resistance 0.2Ω are connected in series. What current will they send through an external resistance of 4Ω (a) 2.5 (b) 6.0 (c) 60 (d) The inductive reactance of an inductor in a ac circuit (in ohms) is (b) 1/ωL (c) (d) ωl 6. The current through a 15 PF capacitor is 0.45 sin (10 8 t ) ma. Write the mathematical expression for the voltage across it. (a) 0.45 sin (10 8 t 0 0 ) V (b) 0.45 sin (10 8 t 45 0 ) V (c) 0.3 sin (10 8 t 45 0 ) V (d) 0.3 sin (10 8 t ) V 7. Find the peak to peak value of an ac voltage whose effective value is 50V rms? (a) 7.07 V (b) V (c) zero (d) 70.7 V 8. In an RLC circuit, phase angle is given by (a) tan [ 1 X L X c ] R (b) sin [ 1 X L X c ] R (c) cos [ 1 X L X c ] R (d) zero 9. In an RC circuit, true power is 300W and reactive power is 1000W. What is the apparent power? (a) 1000VA (b) VA (c) 1000VAR (d) 1000W 10. Three 50 ohm resistors are connected in star across 400V, 3-phase supply. Find phase current (a) 4.5 A (b) 4.62 A (c) 4 A (d) 5 A 11. A DC series generator has a generated emf and terminal voltages of 220V and 210V respectively. If the resistance of the series field is 0.2 Omega what is the resistance of the Armature winding? (a) 0.5 (b) 0.8 (c) 0.75 (d) What type of generator is used for electric welding? (a) differential compound wound dc generator (b) series wound dc generator (c) shunt wound dc generator (d) cumulative compound wound dc generator 13. When speed of a DC motor increases (a) E b and I L decreases (b) E b decreases and I L increases. (c) E b and I L increases (d) E b increases, I L decreases 14. A 230V dc shunt motor has an armature resistance of 0.3 Ω. Calculate the resistance to be connected in series with the armature to limit the armature current to 75 A at starting (a) 2 Ω (b) Ω (c) Ω (d) 0 Ω 15. A 1000/200V transformer takes 0.3 A at p.f of 0.2 on open circuit. Find the magnetizing, and iron loss component of no-load primary current (a) 0.3A, 0.6A (b) 0.294A, 0.6A (c) 0.4A, 0.8A (d) 0.294A, 0.06A 16. The speed of a P-pole synchronous machine in rpm is given by (a) Root of 120f/P (b) 120 P/F (c) 120f/P (d) 120P/f 17. Two main parts of a 3-phase induction motor are (a) rotor and stator (b) slip ring and brushes (c) stator and field (d) rotor and armature 18. A PMMC instrument has a coil of dimensions 15mm12mm The flu density in the sair gap is wb/m 2 and the spring constant is Nm/rad. Determine the number of turns required to produce an angular deflection of 90degrees when a current of 5mA is flowing through the coil (a) 100 (b) 140 (c) 120 (d) The multiplier and the meter coil in a voltmeter are in (a) parallel (b) series-parallel (c) series (d) shunt 20. Power in AC circuits is given by (a) VI (b) VI tan φ (c) VI cos φ (d) VI sin φ

12 1. What is the relationship between the resistance and voltage when the current is kept constant? (a) directly proportional (b) equal to (c) constant (d) inversely proportional 2. In a series circuit, which of the statement is correct (a) total power = sum of powers of each resistor in series (b) total power = zero (c) total power = V I cos φ (d) total power = infinity 3. For a parallel circuit, which statement is correct (a) P T = V S2 R T (b) P T = P 1 + P 2 + P m (c) I 1 + I 2 + I 3 = 0 (d) I i = RT R i +R T I T 4. What is the instantaneous value of V = 5sin (2Π 10 4 t) volts at time (t) = 25µ sec (a) -10V (b) 0V (c) 10V (d) 0.137V 5. A pure inductive coil allows a current of 10 A to flow from a 230v, 50Hz supply. What is the Inductance of the coil? (a) 10/ ΠΩ (b) 26/ ΠΩ (c) 0.23/ΠΩ (d) 23.5/ ΠΩ 6. Average value of sine wave over half a cycle of f(t) = sinwt. (a) V P (b) zero (c) 0.637V P (d) unity 7. Find the peak to peak value of an ac voltage whose effective value is 50V rms? (a) 7.07 V (b) 70.7 V (c) zero (d) V 8. A coil of 0.06H and 2.5 Ω is connected in series with a 6.8 µf capacitor. What is the power factor of the circuit (a) 0.99 (b) 0.8 (c) 0.6 (d) What is the condition for resonance? (a) phase angle is 90 0 lag (b) phase angle is zero (c) phase angle is 90 0 load (d) phase angle is In a star connected alternator, the emf generated in each phase is 3810 volts. Calculate line voltage (a) 600 V (b) 660 V (c) 6600 V (d) 6.6 V 11. A d.c series motor should always be started with load, because it at no-load (a) draws a small current (b) will rotate at dangerously high speed (c) cannot start (d) will not develop high starting torque 12. A compound generator is to supply a load of 250 lamps, each rated at 100W, 250V. The armature, series and shunt field resistances are 0.06, 0.04 and 50Ω respectively. What is the value of armature current when connected in short shunt. (a) A (b) 100A (c) A (d) 105A 13. DC shunt motors should never be started on heavy loads because (a) loads need zero starting torque (b) loads need no starting torque (c) loads need heavy starting torque (d) loads need minimum starting torque 14. While controlling the speed of a dc shunt motor, what should be done to achieve a constant torque drive? (a) applied current should be kept constant (b) applied power should be kept constant (c) applied torque is zero (d) applied voltage should be maintained constant 15. The transformer ratings are usually expressed in terms of (a) KW (b) Volts (c) KVA (d) Amperes 16. A 4-pole, 50Hz synchronous motor runs at (a) 1,500rpm (b) 700rpm (c) 3000rpm (d) 1,490rpm 17. What is the difference between a 3-phase Induction motor and 1-φ induction motor? (a) stator is provided with a single phase between 2poles (b) constriction for 1-φ and 3-φ is same. (c) rotor is provided with a single phase between 2poles (d) both stator and rotor are same 18. The damping torque provided in moving coil instruments is (a) Air friction (b) Eddy current (c) Mechanical (d) Fluid Friction Damping 19. An ammeter is connected with the load (a) In parallel (b) In shunt (c) Across the load (d) In Series 20. In Dynamometer type wattmeter movable coil is called (a) Power coil (b) Potential coil (c) Energy coil (d) Current coil

13 1. In the circuit 1 shown below, find the total current (b) I 1 +I 3 = I 2 +I 4 +I 5 (c) I 1 +I 2 + I 3 +I 4 +I 5 = 0 (d) I 1 +I 2 + I 3 = I 4 +I 5 Figure 1 2. In the circuit 2 given below, V 1 = 7.5V; V 2 = 12.5V then E=? Figure 2 (a) 0V (b) 7.5V (c) 12.5V (d) 20V 3. Determine the total current in the circuit 3 shown below. (a) 0A (b) 10A (c) 5A (d) 1A Figure 3 4. A battery of emf 1.8 volts and internal resistance 1.2Ω is connected to a pair of resistance 4Ω and 6Ωin parallel. Calculate the potential difference of the battery (a) 100V (b) 10V (c) 1.2V (d) 1V 5. The A.C voltage across a 150Ω resistor is 39 sin (2Πtimes10 3 t)v At what value of t does the current through the resistor equal to -0.26A? (a) 7.5 m sec (b) 10 m sec (c) 0.75 m sec (d) 1.0 m sec 6. What is the capacitance needed to produce 1200Ω of reactance when the frequency is 2.3 MHz? (b) 57.7 PF (c) 57.7 µ F (d) 5.77 PF 7. A coil having a resistance of 7 Ω and an inductance of 31.8 mh is connected to 230 v, 50Hz supply. What is the Inductive reactance of the coil? (a) 25 Ω (b) 15 Ω (c) 10 Ω (d) 20 Ω 8. In an RLC series circuit, if the difference between X L and X C increases, then the total (a) impedance reduce (b) resistance increases (c) impedance increases (d) impedance remains unchanged 9. A coil of resistance 100 Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the current through the circuit at resonance. (a) 1A (b) 10A (c) 0.01A (d) 0.1A 10. The algebraic sum of the instantaneous phase voltages of a 3-phase circuit is (b) line voltage (c) twice the phase voltage (d) phase voltage 11. Why is armature core of dc generator laminated? (a) to reduce copper losses (b) to reduce hysteresis loss (c) to reduce friction and windage loss (d) to reduce eddy current loss 12. In a shunt generator Ish = (a) V R sh (b) V-I a R sh (c) V/R sh (d) V+I a R a 13. Which DC motor is preferred for elevators? (a) Shunt motor (b) Differentially compound motor (c) Cumulatively compound motor (d) Series motor 14. Torque and armature current characteristic is (a) straight line (b) circle (c) hyper bolic (d) parabolic 15. If the supply frequency in a transformer is doubled, then (a) copper losses doubles (b) iron losses doubles (c) hysteresis loss also doubles (d) eddy current loss also doubles 16. While running, a synchronous motor is compelled to run at synchronous speed because of (a) Compulsion due to Lenz s law (b) Magnetic locking between stator and rotor poles (c) Induced emf in rotor field winding by stator flux (d) Damper winding in its pole faces 17. What is the difference between a 3-phase Induction motor and 1-φ induction motor? (a) both stator and rotor are same (b) stator is provided with a single phase between 2poles (c) constriction for 1-φ and 3-φ is same. (d) rotor is provided with a single phase between 2poles 18. In the attraction type moving Iron instruments the deflection is proportional to (a) Cube of coil current (b) Square of coil current (c) of coil current (d) Square root of coil current 19. Voltmeter is connected to the load (a) In Diagonal (b) In series (c) In Parallel (d) In series and In Parallel 20. Define meter constant (a) No. of revolutions made per Newton (b) No. of revolutions made per watt (c) No. of revolutions made per hour. (d) No. of revolutions made per kilo-watt hour

14 1. In the above circuit 1, the current coming to node A from 2 Ω resistor is Figure 1 (a) 4A (b) 2A (c) 10A (d) 1A 2. Droop across y Ω shown in figure 2 is (a) 6.66V (b) 0.66V (c) 0.066V (d) 66.66V Figure 2 3. If a 10V battery is connected across the parallel resistor of 3Ω, 5Ω, 10Ω and 20Ω, how much voltage is there across 5Ω resistor? (a) 3V (b) 5V (c) 20V (d) 10V 4. A battery of emf 12V is connected to an external resistance of 20Ω and it is found to have a potential difference of 10V. Find its internal resistance (a) 400Ω (b) 40Ω (c) 0.4Ω (d) 4Ω 5. The A.C voltage across a 150Ω resistor is 39 sin (2Πtimes10 3 t)v At what value of t does the current through the resistor equal to -0.26A? (a) 10 m sec (b) 0.75 m sec (c) 7.5 m sec (d) 1.0 m sec 6. To 318 µ F capacitance, voltage of 230v, 50Hz is connected, what is the value capacitive reactance. (a) 12Ω (b) 8Ω (c) 6Ω (d) 10Ω 7. A coil having a resistance of 7Ω and an inductance of 31.8mH is connected to 230v, 50Hz supply. What is the impedance of the coil. (a) 12.2Ω (b) 12.8Ω (c) 12.6Ω (d) 12.4Ω 8. A 318 µf capacitor is connected across a 230V, 50Hz system. Find RMS value of current (a) 30A (b) 33A (c) 1A (d) 23A 9. Q - factor of a series resonant circuit is (a) voltage / current (b) voltage across L or C / Applied voltage (c) power factor (d) L / C 10. A balanced delta connected load of (2+j3) ohms per phase is connected to a balanced 3-phase 440V supply. The phase current is 10A. Find active power. 11. (a) 50KW (b) 100KW (c) 7.26KW (d) 10KW For the figure 11 shown, the total resistance between terminals a and is given by Figure 11 (a) R a /R (b) Ra-R (c) R a +R (d) R a R/Ra+R 12. In a short shunt compound generator, the terminal voltage is equal to (a) E g I L R se (b) E g I a R a I L R se (c) E g I a R a + I L R se (d) E g + I a R a 13. For DC series motor, speed-torque characteristic (a) hyperbolic (b) parabolic (c) straight line (d) zero 14. Which relation is correct? (a) N α ω/eb (b) N α 1/I (c) N α 1/Eb (d) N α Eb 15. Material used for construction of transformer core is usually (a) Silicon steel (b) Copper (c) Aluminum (d) Wood 16. The rotor preferred for alternators applied to hydraulic turbines are (a) Solid rotor type (b) Laminated rotor type (c) Salient pole type (d) Cylindrical rotor type 17. A 3-phase induction motor is wound for 4-poles and supplied from 50Hz.calculate the synchronous speed (a) 1500rpm (b) 1200rpm (c) 200rpm (d) 1000rpm 18. The shape of the coil used in permanent magnet moving coil instruments is (a) Elliptical (b) Circular (c) Parabola (d) Rectangular 19. Ammeter is connected in in the circuit whose current is to be measured (a) shunt-series (b) series (c) series-shunt (d) shunt 20. The units of power is (a) Newton (b) joules (c) watt hour (d) watts

15 1. Kirchoff s current law is based on (a) law of conservation of energy (b) law of conservation of electric charge (c) law of conservation of current (d) law of conservation of power 2. Find the voltage across 30Ω resistor shown in figure below 2 (a) 60V (b) 40V (c) 50V (d) 45V Figure 2 3. When a 1.2KΩ resistors, 100Ω resistor, 1KΩ resistor and 50 Ω resistor are in parallel, the total resistance is less than (a) 1.2Ω (b) 100Ω (c) 1KΩ (d) 50Ω 4. A battery of emf 1.8 volts and internal resistance 1.2Ω is connected to a pair of resistance 4Ω and 6Ωin parallel. Calculate the potential difference of the battery (a) 100V (b) 1V (c) 10V (d) 1.2V 5. The current in a 2.2 k Ωresistor is I = 5 sin (2 Π 100t ) ma. What is the effective value of resistor voltage? (a) 778.0V (b) 7.78V (c) 77.8V (d) 0.778V 6. What is the capacitance needed to produce 1200Ω of reactance when the frequency is 2.3 MHz? (a) 5.77 PF (b) 57.7 µ F (c) zero (d) 57.7 PF 7. A choke coil takes a current of 2.5 A when connected across a 250v, 50Hz mains and consumes 400W. What is the power factor of the circuit? (a) 0.64 lag (b) 0.68 lag (c) 0.7 lag (d) 0.67lag 8. A capacitor of capacitance 79.5 µf is connected in series with a non inductive resistance of 30Ω across 100v, 50Hz supply. Find the capacitive reactance of the circuit (a) 47Ω (b) 40Ω (c) 42Ω (d) 38Ω 9. A coil of resistance 100 Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the current through the circuit at resonance. (a) 0.1A (b) 10A (c) 1A (d) 0.01A 10. In a balanced Wye connection, total 3φ power in terms of phase quantities in (a) V P h I P h (b) 3 V P h I P h cos φ (c) 3 V P h I P h cos φ (d) V P h I P h cos φ 11. A d.c series motor should always be started with load, because it at no-load (a) cannot start (b) draws a small current (c) will rotate at dangerously high speed (d) will not develop high starting torque 12. The factor that is not responsible for drop in terminal voltage of a dc shunt generator on load is (a) armature reaction (b) armature resistance drop (c) commutation (d) field weakening due to armature reaction and armature resistance drop 13. Which DC motor is generally preferred for cranes and hoists? (a) Shunt motor (b) Series motor (c) Cumulative compound motor (d) Differentially compound motor 14. A 3 point starter is considered as suitable for (a) All DC motors. (b) Shunt motors (c) Shunt, compound and series motors (d) Shunt as well as compound motors 15. The flux involved in the emf equation of a transformer has (a) total value (b) rms value (c) maximum value (d) average value 16. If P is the number of poles, f = frequency in Hz, N=Speed in rpm, the relationship between the three for a synchronous alternator is given by (a) f = P N 120 Hz (b) N = fp 120 rpm (c) p = fn 120 poles (d) f = NP 60 Hz 17. For which Induction motor the speed can be controlled from rotor side? (a) Slip ring (b) Shunt Motor (c) Squirrel case (d) Squirrel case and slip ring 18. The shape of the iron piece used in Attraction type moving iron instruments is (a) Circular (b) Oval (c) Elliptical (d) Rectangular 19. An ammeter is used to measure the flow of in a circuit (a) Current (b) Energy (c) Voltage (d) Power 20. Define meter constant (a) No. of revolutions made per kilo-watt hour (b) No. of revolutions made per Newton (c) No. of revolutions made per watt (d) No. of revolutions made per hour.

16 1. A battery has an emf of 12.9 volts and supplies a current of 3.5 A. What is the resistance of the circuit? (a) Ω (b) 3.69 Ω (c) 3.5 Ω (d) 16.4 Ω 2. A series circuit consists of a 4.7 kω, 5.6kΩ, 9kΩ and 10kΩ resistor. Which resistor has the most voltage across it? (a) 9 kω (b) 4.7 kω (c) 10 kω (d) 5.6 kω 3. Power in a parallel circuit is equal to (a) product of all powers (b) sum of all resistors in parallel (c) sum of all powers in parallel (d) product of all resistors in parallel 4. A battery of emf 12V is connected to an external resistance of 20Ω and it is found to have a potential difference of 10V. Find its internal resistance (a) 40Ω (b) 4Ω (c) 400Ω (d) 0.4Ω 5. The current in a 2.2 k Ωresistor is I = 5 sin (2 Π 100t ) ma. What is the effective value of resistor voltage? (a) 77.8V (b) 7.78V (c) 778.0V (d) 0.778V 6. To 318 µ F capacitance, voltage of 230v, 50Hz is connected, what is the value capacitive reactance. (a) 6Ω (b) 10Ω (c) 12Ω (d) 8Ω 7. The equation of 50 Hz ac sinusoidal current having an rms value of 10A is (a) [2Π 50 (t φ)] (b) 10[2Π 50 (t + φ)] (c) 14.4 sin (2Π 50 t) (d) 10 sin (2Π 50 t) 8. A 318 µf capacitor is connected across a 230V, 50Hz system. Find RMS value of current (a) 30A (b) 1A (c) 33A (d) 23A 9. A coil of resistance 100 Ω and 100 µh is connected in series with a 100 PF is connected to a 10V, variable frequency supply. What is the current through the circuit at resonance. (a) 1A (b) 0.1A (c) 10A (d) 0.01A 10. A balanced delta connected load of (2+j3) ohms per phase is connected to a balanced 3-phase 440V supply. The phase current is 10A. Find active power. (a) 10KW (b) 100KW (c) 7.26KW (d) 50KW 11. A d.c series motor should always be started with load, because it at no-load (a) will rotate at dangerously high speed (b) cannot start (c) will not develop high starting torque (d) draws a small current 12. The factor that is not responsible for drop in terminal voltage of a dc shunt generator on load is (a) armature resistance drop (b) commutation (c) field weakening due to armature reaction and armature resistance drop (d) armature reaction 13. Which one of the following is not the function of pole shoes in a DC machine? (a) To reduce eddy current loss (b) To spread out flux for better uniformity (c) To reduce the reluctance of the magnetic path. (d) To support the field coils 14. Which relation is correct? (a) N α 1/I (b) N α ω/eb (c) N α Eb (d) N α 1/Eb 15. If the supply frequency in a transformer is doubled, then (a) copper losses doubles (b) eddy current loss also doubles (c) hysteresis loss also doubles (d) iron losses doubles 16. A Synchronous motor can be used as a synchronous capacitor when it is (a) Under excited (b) Over loaded (c) Over excited (d) Under loaded 17. A 3-phase induction motor is wound for 4-poles and supplied from 50Hz.calculate the synchronous speed (a) 1500rpm (b) 1200rpm (c) 200rpm (d) 1000rpm 18. In a moving iron instrument, deflecting torque is proportional to (a) square of voltage (b) voltage (c) square of operating current (d) current 19. Voltmeter is used to measure the between two points of a circuit. (a) Current (b) Potential difference (c) Energy (d) Power loss 20. In the power equation of an ac circuit, the values of voltage and current are in form (a) minimum value (b) direct (c) rms (d) maximum value