当前测试题类型单选
1. For supplying more electricity, what kind of voltage is used?
A14V AC power
B115V AC power
C14V DC power
D28V DC power
回答错误你的答案正确答案B
2. In a metal airplane, what is used as a return wire?
Aaircraft frame
Bcopper wire
Caluminum wire
Diron wire
回答错误你的答案正确答案A
3. Which is better conductor?
Acopper
Baluminum
Csteel
D(NO)
回答错误你的答案正确答案A
4. Why the wiring is coated [涂上、蒙上]with tin, silver, or nickel?
ATo help prevent oxidation
BTo make the wire har
CTo decrease the resistance of wire
D(NO)
回答错误你的答案正确答案A
5. If a transformer变压器has turns ratio of 12, and inputs of 240 V and 5 amps, the output voltage is ( )
A60V
B120V
C240V
D480V
回答错误你的答案正确答案D
6. If a transformer has turns ratio of 12, and inputs of 240 V and 5 amps, the output current is ( )
A2.5A
B5A
C10A
D20A
回答错误你的答案正确答案A
7. In star connection three-phase AC system, phase voltage is 115V, the line voltage is ( )
A55V
B115V
C200V
D230V
回答错误你的答案正确答案C
8. In star connection连接three-phase AC system, phase current is 100A, the line current is ( )
A50A
B100A
C173A
D200A
回答错误你的答案正确答案B
9. In delta三角形connection three-phase AC system, phase current is 100A, the line current is ( ) A50A
B100A
C173A
D200A
回答错误你的答案正确答案C
10. A transformer rectifier unit (TRU) is used to convert ( )
ADC power to AC
BAC power to DC
CDC power to DC
DAC power to AC
回答错误你的答案正确答案B
11. A frequency-wild generator can be used to operate circuits containing ( )
Aresistive components
Binductive components
Ccapacitive components
D(NO)
回答错误你的答案正确答案A
12. If an over voltage occurs发生, ( ) reset复位may be attempted尝试，试图.
Aone
Btwo
Cthree
Dfour
回答错误你的答案正确答案A
13. On modern aircraft, the Constant Speed Drive Unit (CSDU) and generator are normally combined as one unit, which is known as ( )
ATRU
BIDG
CVSCF
DINV
回答错误你的答案正确答案B
14. The Differential Protection circuit is used to monitor ( )
Aline-to-earth faults
Bunder-voltage faults
Cover-voltage faults
Dunder-frequency faults
回答错误你的答案正确答案A
15. What kind of electrical power is used in relay coil?( )
ADC voltage
BAC voltage
CDC or AC voltage
D(NO)
回答错误你的答案正确答案A
16. In a LA battery, the active material on a charged positive plate is( )
ALead Dioxide (PbO2)
BLead (Pb)
CLead sulphate (PbSO4)
D(NO)
回答错误你的答案正确答案A
17. In a LA battery, the active material on a charged negative plate is ( ) ALead Dioxide (PbO2)
BLead (Pb)
CLead sulphate (PbSO4)
D(NO)
回答错误你的答案正确答案B
18. For a nickel-cadmium battery,the active material on the positive plate is ( ) Anickel hydroxide
Bcadmium hydroxide
CNickel
Dcadmium
回答错误你的答案正确答案A
19. For a nickel-cadmium battery,the active material on the negative plate is ( ) Anickel hydroxide
Bcadmium hydroxide
CNickel
Dcadmium
回答错误你的答案正确答案D
20. In a DC generator, which opponent is used to convert 转换AC to a DC? ( )
