Preview Question paper 1 (101-120)

Q.101. A. alternator is supplying a load of 300kW of a power factor of 0.6 lagging . If the power factor is raised to unity , how many kilowatts can alternator supply for the same kVA loading
a.)100kW
b.)200kW✔
c.)300kW
d.)500kW

Q.102. for transmission line which of the following relation is correct  ?
a.)AD-BC=1✔
b.)AC-BD=1
c.)BA-CD=1
d.)BC-AD=1

Q.103. match the following
Types of transmission line types of relay
 preferred
i. Short line               1. Ohm relay
ii. Medium line          2. Reactance relay
iii. Long line.               3. Mho relay
a.) a-1, b-2,c-3
b.)a-2,b-1,c-1✔
c.)a-3, b-2,c-1
d.)a-1,b-1,c-1

Q.104. High Voltage Transmission (HVDC transmission) is mainly used for
a.)Bulk power transmission for very long distance ✔
b.)Interconnecting to system with the same nominal frequency
c.)Eliminating reactive power requirement in the operation
d.)Minimizing harmonics at the converter station

Q.105. Ferranti effect is seen in which transmission line?
a.)Long transmission line ✔
b.)Medium transmission line
c.)short transmission line
d.) Both A and B

Q.106. SCR is a device
a.)Semi-controlled✔
b.)Full-controlled
c.)Uncontrolled
d.)None of these

Q107. For a 3Φ transmission line transmission efficiency of a line decrease with
a.)Increase in load power factor
b.)Decrease in load power factor✔
c.)Does not vary with power factor
d.)Increase in Load current

Q.108. 3Φ synchronous  motor has
a.)High starting torque
b.)Low starting torque
c.)No starting torque✔
d )Low starting current

Q.109. In a synchronous motor
a.)The rotor mmf and stator mmf are stationary with respect to each other ✔
b.)Stator mmf rotates slightly faster then rotor mmf
c.)Rotor mmf rotates slightly faster in comparison to stator mmf
d.)None of these

Q.110. When does a synchronous motor operate with leading power factor electric current?
a.)While it is under excited
b.)While it is over excited✔
c.)While it is critically excited
d.)While it is heavily loaded

Q.111. The use of _____instrument is merely confined within laboratories as standardizing instrument
a.)Indicating
b.)Absolute✔
c.)Recording
d.)Integrating

Q.112. Slip of induction motor is 0.02 and the stator supply frequency is 50Hz . The frequency of rotor induced e.m.f. will be
a.)10Hz
b.)50Hz
c.)1Hz✔
d.)25Hz

Q.113. The watt meter reads 30.34W. The absolute error in the measurement is 2.22W . What is the true value of power
a.)32.56W✔
b.)28.12
c.)25.45
d.)None of these

Q.114.A resistor and an  inductor are connected in series across a voltage source. which two parameter in that circuit decreases if the frequency of source increase
a.)VL and Z
b.)Z and I
c.)VR and I✔
d.)VL and VR

Q.115. Diatance relays operation is depend upon
a.)Ratio of current to current
b.)Ratio of voltage to current✔
c.)Ratio of voltage to voltage
d )Ratio of voltage to resistance

Q.116. Harmonic distortion of signal is produced in RC  coupled amplifier . The probable  cause is
a.)Transistor itself✔
b.)Power supply Vcc
c.)Coupling capacitor Cc
d.)Biasing resistor R1 & R2

Q117. When 't' is thickness of sheet , the top diameter of spot welding is usually
a.) 2t
b.) t
c.) √t✔
d.) 1/t

Q.118. For tramways, the return circuit is through
 a.)Cable
b.)Rails✔
c.)Neutral
d.)Common earthing

Q 119. The rectifier which require the minimum amout of filtering is
a.)Half wave rectifier
b.)Full wave rectifier
c.)Voltage doubler
d.)SCR half wave rectifier✔

Q. 120. A device whose chercterstics are close to ideal voltage source
a.) Diode
b.) FET
C.)Transistor in CB
d.)Zener diode✔