113. In case of conlactors, the duty in which the main contacts remain closed for a period bearing a definate relation to the no-load periods, is known as
A. Standard duty
B. Intermittent duty
C. Temporary duty
D. Un-interrupted duty

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114. In case of contactors the ratio of the in-service period to the entire period, expressed as a percentage is known as
A. duty
B. load factor
C. class of contact
D. none of these

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115. Heat control switches find applications in
A. three-phase induction motors
B. single phase motors
C. transformers
D. cooling yanges.

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116. A magnetic amplifier can be used for the control of
A. current
B. voltage
C. speed
D. all of these

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117. In a contactor, overheating of contacts may result from
A. high inductive loads
B. copper oxide on contacts
C. carrying load continuously for a longer time
D. all of these

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118. According to Indian Electricity rules, extra high voltage implies voltage exceeding
A. 440V
B. 66kV
C. 33kV
D. 110kV

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119. Non metallic conduits for wiring are generally made of
A. rubber
B. cork
C. wood
D. PVC

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