更多"[单选题]These figures show that the de"的相关试题:
[单选题]The figures show that our economy is healthy and we are ______ to achieve sustainable and balanced growth.
A.in track
B.at track
C.off track
D.on track
[判断题]电阻R1,R2并联,已知R1>>R2,并联后的等值电阻近似等于R1,即R≈R1。
A.正确
B.错误
[简答题] A whole life insurance policy pays a death benefit if the policyholder dies.
[填空题]已知R1=300Ω,R2=R3=600Ω。求R1、R2和R3并联的等效电阻R=______Ω。
[判断题]R717、R22、R134a在相同工況下排气温度由低到高的顺序为R717>R22>R134a。( )22.R717的最大压力差为pk-po≤1.6MPa。( )
A.正确
B.错误
[单选题]Her children’s death is a blow on her.
A. insignificant
B. fatal
C. indifferent
D. non-fatal
[单选题]We were(saddened) to hear of the death of your mother.括号内单词的含义为。
A.crazy
B. sad
C. excited
D. serious
[单选题]已知:R1=30Ω、R2=20Ω、R3=10Ω,R1与R2并联后再与R3串联,最后这条支路总电阻为( )。
A.(R1R2/R1+R2)+R3=22Ω
B.R1+R2+R3=60Ω
C.R1+R2=R3=10Ω
D.R2+R3=R1=30Ω
[单选题]R1和R2 为两个串联电阻,已知R1=4R2,若R1上消耗的功率为1W,则R2上消耗的功率为( )。
A.5W
B.20W
C.0.25W
D.4W
[单选题]电阻R1、R2串联后接在直流电路中,若R1=2R2,则R1两端的电压是R2两端电压的(___)。
A.2倍
B.4倍
C.1/4倍
D.1/2倍
[单选题]电阻R1、R2串联后接在直流电路中,若R1=1/2R2,则R1两端的电压是R2两端电压的(___)。
A.2倍
B.4倍
C.1/4倍
D.1/2倍
[判断题]R134a的热力性质与R12很接近,在使用R12的制冷装置中、可使用R134a替代R12而不需要对设备做任何改动。( )
A.正确
B.错误