一个正弦交流电压波形如下图所示,其瞬时值表达式为。
A: u=10sin(ωt-π/2)V
B: u=-10sin(ωt-π/2)V
C: u=10sin(ωt+π)V
D: u= -10sin(ωt+π)V
A: u=10sin(ωt-π/2)V
B: u=-10sin(ωt-π/2)V
C: u=10sin(ωt+π)V
D: u= -10sin(ωt+π)V
举一反三
- 一正弦交流电压波形如图所示,其瞬时值表达式为()伏。 A: u=10sin(ωt-π/2) B: u=10sin(ωt+π) C: u=-10sin(ωt-π/2) D: u=-10sin(ωt+π)
- 一正弦交流电压波形如图所示,其瞬时值表达式为()伏。 A: u=10sin(ωt-π/2)\n B: u=10sin(ωt+π)\n C: u=-10sin(ωt-π/2)\n D: u=-10sin(ωt+π)
- u=- 10sin(5πt+ 10)V超前i= 5cos(5πt - 150)A的相位差是
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