更多"A circuit breaker and a fuse have a"的相关试题:
[单项选择]A circuit breaker and a fuse have a basic similarity in that they both （）.
A. can be reset to energize the circuit
B. should open the circuit when overloaded
C. will burn out when an over current flow develops
D. All of the above
[单项选择]A circuit breaker differs from a fuse in that a circuit breaker （）.
A. melts and must be replaced
B. is enclosed in a tube of insulating material with metal ferrules at each end
C. gives no visual indication of having opened the circuit
D. trips to break the circuit and may be reset
[单项选择]Prior to closing the breaker when paralleling two AC generators, the recommended practice is to have the frequency of the incoming machine （）
A. slightly less than the line frequency
B. the same as the line frequency
C. slightly greater than the line frequency
D. All of the above
[单项选择]A fuse that blows often should be replaced only with a fuse of （）.
A. the recommended current and voltage rating
B. higher current and voltage rating
C. higher current and lower voltage rating
D. lower current and higher voltage rating
[单项选择]Since fuse elements are made of zinc or any alloy of tin and lead, the melting point of the fuse element must be （）.
A. higher than that of copper
B. lower than that of copper
C. equal to that of copper
D. reached when the conductor it is protecting becomes "white hot"
[单项选择]The part of a fuse that melts and opens the circuit is made of （）.
A. copper and antimony
B. steel and babbitt
C. aluminum or beryllium alloy
D. zinc or an alloy of tin and lead
[单项选择]（）by an ice-breaker, it is important to maintain a continuous listening watch on the appropriate VHF channel and to maintain a proper look-out for sound and visual signals.
A. which is assisted
B. that assist you
C. when you assisted
D. when being assisting
[多项选择]在PMS中，可以用CIM模型中Fuse对象表示的是（）
A. 变电熔断器
B. 配电跌落式熔断器
C. 配电熔断器
D. 变电手车刀
[单项选择]在Visual Basic环境下，当写一个新的Visual Basic程序时，所做的第一件事是（）。
A. 编写代码
B. 新建一个工程
C. 打开属性窗口
D. 进入VisualBasic集成开发环境
[单项选择]The basic collision avoidance display presented by CASII is designed for easy interpretation and（）of possible collision threat situations.
A. full confirmation
B. precise appreciation
C. immediate assessment
D. timely recognition
[单项选择]Basic emergency care for third degree electrical burn is to（）.
A. flood the burned area with warm water for two minutes
B. brush away the charred skin and wrap the burned area
C. cover the burned area with a clean cloth and transport the patient to a medical facility
D. apply ointment or spray to the burned area and wrap with a clean cloth
[单项选择]在Visual Basic应用程序中（）
A. 过程的定义可以嵌套，但过程的调用不能嵌套
B. 过程的定义不可以嵌套，但过程的调用可以嵌套
C. 过程的定义和过程的调用均可以嵌套
D. 过程的定义和过程的调用均不能嵌套
[单项选择]The basic process of biological sewage treatment consists of the liquor either by bubbling air through it or by agitating the surface（）
A. oxygenating
B. oxidizing
C. deoxygenating
D. proportioning
[单项选择]The basic function of the centrifugal pump impeller is to （）.
A. directly increase the pressure of the liquid being pumped
B. directly increase the velocity of the liquid being pumped
C. convert the potential energy of the liquid to kinetic energy
D. separate air from the liquid being pumped
