A、μ<sub>1sub>〈μ<sub>2sub> B、μ<sub>1sub>〉μ<sub>2sub> C、σ<sub>1sub>〈σ<sub>2sub> D、σ<sub>1sub>〉σ<sub>2sub>
A、μ<sub>1sub>〈μ<sub>2sub> B、μ<sub>1sub>〉μ<sub>2sub> C、σ<sub>1sub>〈σ<sub>2sub> D、σ<sub>1sub>〉σ<sub>2sub>
A、M<sub>1sub>=M<sub>2sub>=M<sub>0sub> B、M<sub>1sub>=M<sub>2sub>=2M<sub>0sub> C、M<sub>1sub>=M<sub>2sub>=1/2M<sub>0sub> D、M<sub>1sub>+M<sub>2sub>=2M<sub>0sub>
A、r<sub>1sub>=r<sub>2sub>=0,L<sub>1sub>=L<sub>2sub>=M=0 B、r<sub>1sub>=r<sub>2sub>=0,L<sub>1sub>=L<sub>2sub>=M=∞ C、r<sub>1sub>=r<sub>2sub>=∞,L<sub>1sub>=L<sub>2sub>=M=0 D、r<sub>1sub>=r<sub>2sub>=∞,L<sub>1sub>=L<sub>2sub>=M=∞
A、VT<sub>1sub>导通,TV<sub>2sub>截止 B、VT<sub>1sub>截止,VT<sub>2sub>导通 C、VT<sub>1sub>导通,VT<sub>2sub>导通 D、VT<sub>1sub>截止,VT<sub>2sub>截止
A、sqrt(a<sub>1sub>b<sub>1sub>),inf B、sqrt(a<sub>2sub>b<sub>2sub>),inf C、sqrt(a<sub>1sub>b<sub>1sub>),sqrt(a<sub>1sub>b<sub>1sub>) D、1,1
A、串联型稳压电路如图所示,设V<sub>BE2sub>=0.7V,稳压管V<sub>zsub>=6.3V,R<sub>2sub>=350Ω。
(1)若要求V<sub>Osub>的调节范围为10~20V,则R<sub>1sub>及R<sub>wsub>应选多大?
(2)若要求调整管T<sub>1sub>的压降V<sub>CE1sub>不小于4V,则变压器次级电压V<sub>2sub>(有效值)至少应选多大?(设滤波电容C足够大)。
c="https://img.ppkao.com/2019-04/wuacheng/2019042616184549829.jpg" />
A、α<sub>1sub>=α<sub>2sub> B、α<sub>2sub>>α<sub>2sub> C、α<sub>1sub><α<sub>2sub> D、与α<sub>1sub>和α<sub>2sub>无关
A、对任意实数,都有p<sub>1sub>=p<sub>2sub> B、对任意实数,都有p<sub>1sub>
sub>2 C、对任意实数,都有p<sub>1sub>>p<sub>2sub> D、对任意实数,都有p<sub>1sub>≠p<sub>2sub>
sub>
A、R<sub>Asub>:R<sub>Bsub>=2,T<sub>Asub>:T<sub>Bsub>=2 B、R<sub>Asub>:R<sub>Bsub>=1/2,T<sub>Asub>:T<sub>Bsub>=1 C、R<sub>Asub>:R<sub>Bsub>=1,T<sub>Asub>:T<sub>Bsub>=1/2 D、R<sub>Asub>:R<sub>Bsub>=2,T<sub>Asub>:T<sub>Bsub>=1
A、S<sub>0sub>>S<sub>1sub>>S<sub>2sub>>S<sub>3sub> B、S<sub>0sub>>S<sub>2sub>>S<sub>1sub>>S<sub>3sub> C、S<sub>0sub>>S<sub>1sub>=S<sub>2sub>>S<sub>3sub> D、S<sub>0sub>>S<sub>2sub>>S<sub>3sub>>S<sub>1sub>