A.400V, 0.02s | B.200V,0.02s | C.400V,0.08s | D.200V,0.08s |
A.U=220V,I=0.39A | B.U=220V,I=0.55A |
C.U=311V,I=0.55A | D.U=311V,I=0.39A |
A.最大值仍为Um,而频率大于f |
B.最大值仍为Um,而频率小于f |
C.最 大值大于Um,而频率仍为f |
D.最大值小于Um,而频率仍为f |
A.该交变电流的电压瞬时值的表达式为u=100sin(25t)V |
B.该交变电流的频率为25 Hz |
C.该交变电流的电压的有效值为100 V |
D.若将该交流电压加在阻值为R=100 Ω的电阻两端,则电阻消耗的功率是50 W |
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