FUNCTION -5 (ELECTRICAL)

91. Ambient temperature rise in transistor
    1. life loss
    2. life increases
    3. stable
    4. none

ANS.: A

93. The amount of current needed for full protection in case of ICCP system for a particular ship will be most affected by
    1. wetted surface area
    2. quality and condition of protection pain coating
    3. speed of the ship
    4. sea water temperature

ANS.: 1,2,3,4

94. Which of the following consider to be the safest protection from static electricity discharge when connecting or disconnecting cargo hose and metal arms?
    1. insulating flange on the length of the non-conducting hose
    2. switching off ICCP
    3. ship shore bonding cable
    4. none of this above

ANS.: C

95. Class A amplifier percentage?
    1. 8%
    2. 50%
    3. 25%
    4. 75%

ANS.: C

96. In properly biased npn transistor most free electron from emitter
    1. recombine with hole and base
    2. recombine with emitter itself
    3. stopped with emitter itself
    4. pass through the base to collector

ANS.: D

97. Which of the following true regards to syncronoscope
    1. the coil produce 3 phase rotating field
    2. the coil produce 1 phase rotating field
    3. the rotating armature has 2 coil winding perpendicular to each other
    4. the rotating armature has coil parallel to each other

ANS.: B,C

98. Characteristic of laser light
    1. Coherent
    2. Collimated
    3. Monochromatic
    4. all the above

ANS.: D

99. Which of the following used in earth neutral system
    1. netural earthing resistor
    2. fuse
    3. overcurrent
    4. transformer

ANS.: A

100. 3 phase insulated earth system one of the path contact with hull
     1. earthed
     2. short circuit or grounded
     3. a and b
     4. none of the above

ANS.: A

101. Which of the device protect the generator from over load
     1. relay on switch
     2. governor
     3. ACB
     4. overspeed trip on prime mover

ANS.: D

102. Which is true
     1. over current relay act faster than Fuse
     2. over current relay trip the contactor on over load depend on over load setting
     3. fuse meant for protection against over load upto staled current
     4. none of these above

ANS.: B

103. N type semiconductor doping substance
     1. antimony
     2. phosphorus
     3. arsenic
     4. all the above

ANS.: D

104. Class B amplifier output
     1. distortion free
     2. output of full wave rectifier
     3. output of half wave rectifier
     4. none

ANS.: C

105. While doping the semiconductor is adding impurities, why it is called impurities
     1. it change the crystal structure of the semiconductor
     2. it change the chemical free semiconductor
     3. it prevent the flow of free electrons
     4. all of the above

ANS.: A

106. Wound rotor motor changing the speed torque characteristic control and speed control purpose
     1. use AVR with motor
     2. use changing no of poles in a motor
     3. use external resistor in a rotor circuit
     4. use external resistor in a stator circuit

ANS.: C

107. Grounding occur in the electrical machinery as a result of insulation failure.
     1. deterioration through moisture
     2. excessive heat
     3. external period of vibration
     4. all of the above

ANS.: D

108. Unique feature of a cc transistor amplifier circuit is
     1. step up the impedance level
     2. dose not increase the signal voltage
     3. act as an impedance matching device
     4. all of the above

ANS.: D

109. Capacitor and resistor connected in series with the sine wave generator frequency is set so that the capacitor reactance is equal to the resistance and thus equal amount of voltage appears across each component, what happen when frequency. What happens if the frequency is increased?
     1. Voltage across the resistor became higher than voltage in the capacitor
     2. voltage across the capacitor became higher than voltage in the resistor
     3. voltage across capacitor remain same as the voltage across the resistor
     4. cannot determine

ANS.: A

110. Advantage of nickel cadmium battery
     1. high voltage
     2. fewer cell needed for same voltage
     3. full charge for long time
     4. less expensive

ANS.: C

112. 3 phase, if it is connected insulated earth system to the ship’s hull
     1. short circuit
     2. earth fault
     3. both a and b
     4. neither a or b

ANS.: B

113. What will be in motor, for electro steering gear?
     1. Fuse
     2. overload Alarm
     3. power failure alarm
     4. overload trip

ANS.: D

114. Impurities in semiconductor
     1. doping
     2. biasing
     3. alloying
     4. none of the above

ANS.: A

115. Capacitor banks are connected with ac induction motor
     1. in parallel
     2. in series.
     3. not connected
     4. can be connected either way –series / parallel.

ANS.: A

116. A control action which produces a corrective signal relative to the length of time the controlled variable has been away from the set point, is known as
     1. Integral action
     2. Proportional action
     3. Rate action
     4. Derivative action

ANS.: A

117. What happens to the amount of energy stored in the electromagnetic field when the current through an inductor is cut in half?
     1. Is reduced to one fourth
     2. Is reduced to one half
     3. Doubles
     4. Quadruples

ANS.: A

118. Doping materials are called impurities because they
     1. Decrease the number of charge carriers
     2. Change the chemical properties of semiconductors
     3. Make semiconductors less than 100% pure
     4. Alter the crystal structures of pure semiconductors

ANS.: D

119. The output of class B amplifier
     1. Is distortion free
     2. Consists of positive half cycle only
     3. Is like the output of a full wave rectifier
     4. Comprises short duration current pulses

ANS.: B

120. Which of the following are not appropriate precautions to be taken prior to the overhaul of the motor on a ship?

1. Prove dead at starter / motor terminals
2. Post caution signs all over the ship
3. Make sure work area is clear
4. Remove overload relay
5. Isolate the motor
6. Remove motor fuses

1. iv and vi
2. i and ii
3. i and v
4. ii and iv

ANS.: D