更多"A heater in the circuit facilitates"的相关试题:
[单项选择]An electric heater built into some smaller diesel engines is used to （）.
A. raise lube oil viscosity for easier starting in cold weather
B. increase air inlet temperature
C. increase compression ratio
D. increase jacket water temperature for easier starting in cold weather
[单项选择]The main purpose of an electric space heater installed in a large AC generator is to （）
A. prevent the windings from becoming brittle
B. prevent moisture from condensing in the windings during shutdown
C. prevent acidic pitting of the slip rings
D. keep the lube oil warm for quick starting
[名词解释]SELV回路（SELV circuit）
[单项选择]A re-heater in an air conditioning system functions to （）.
A. control inlet air temperature
B. control inlet air volume
C. maintain relative humidity at 15%
D. restore conditioned air temperature to a comfortable level
[单项选择]For a flash type evaporator, the seawater heater will have to maintain a enough temperature to minimize scale formation（）
A. lower
B. higher
C. low
D. high
[单项选择]The fuel booster pump and steam to fuel heater, together with fuel pipe heater tracer line should be shut off as soon as the （） order is acknowledged.
A. finished with engines
B. stop
C. stand by
D. full ahead
[单项选择]A re-heater, as used in an air conditioning system, is designed to control the （）
A. chilled water temperature
B. dew point temperature
C. primary air temperature
D. dry bulb temperature
[单项选择]Capacitance is the property of an electric circuit opposing a change in the （）
A. current in the circuit
B. voltage in the circuit
C. inductance in the circuit
D. resistance in the circuit
[单项选择]The total resistance of a parallel circuit is always （）.
A. larger than the greatest branch resistance
B. smaller than the lowest branch resistance
C. equal to the sum of the individual branch resistances
D. one-half the sum of the individual branch resistances
[单项选择]A ground in an electrical circuit outside the engine room （）.
A. cannot be detected tinder normal conditions
B. is of no consequence to engineering personnel
C. is indicated at the branch circuit breaker panel
D. is indicated by the ground detecting lamps on the main switchboard
[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]In a series circuit, which value will remain unchanged at all places in the circuit?（）
A. Voltage
B. Current
C. Resistance
D. Inductance
[单项选择]A transformer in an electric circuit serves to （）
A. generate its own electrical power
B. transform electrical energy into mechanical energy
C. increase or decrease circuit voltage as required
D. convert AC current to DC current
[单项选择]In a simple series circuit, the entire source voltage will drop across （）
A. the resistor next to the negative terminal
B. a short circuit
C. the resistor next to the positive terminal
D. an open circuit
[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]A resistance in a circuit of unknown value is to be tested using the voltmeter/ammeter methodTherefore, the meters should be connected with（）.
A. both meters in series with the resistance
B. both meters in parallel with the resistance
C. the ammeter in series and the voltmeter in parallel with the resistance
D. the ammeter in parallel and the voltmeter in series with the resistance
[单项选择]In a three-phase circuit, the phase voltages are （）
A. 120°apart
B. 160°apart
C. 180°apart
D. 360°apart
