如图所示 换路前后的uc怎么求出
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三要素法:
1)换路前,Uc(0) = 0;
2)换路后的 t=∞ 时,Uc(∞) = Uab = Uac + Ucb;
3)时间常数中的电阻 R = (R1//R3) + (R2//R4);
然后代入全响应公式,即得 Uc(t) 表达式;
等你理解了这些,再往下说
好
追答1)从上述解得:Uc(t)=6-6e^(-t/τ);
而电流是电压的导数,即: ic(t) = C*dUc(t)/dt = C*(6/τ)*e^(-t/τ) = e^(-t/τ);
2)电路中的其余参量继续套用三要素法:
电源电流:i(0) = i1 + i2 = E/(R1+R3) + E/(R2+R4) =3/2;
i(∞) = E/(R1//R2 + R3//R4) = 12/8 = 3/2;
所以:i(t) = 3/2,为恒定值,与时间无关;