A、r=r<sub>1sub> B、r>r<sub>1sub> C、r<r<sub>1 D、r≤r<sub>1sub>r<sub>
A、滚子半径r<sub>rsub>≤凸轮理论廓线外凸部分的最小曲率半径ρ<sub>minsub> B、滚子半径r<sub>rsub>≥凸轮理论廓线外凸部分的最小曲率半径ρ<sub>minsub> C、滚子半径r<sub>rsub><凸轮理论廓线外凸部分的最小曲率半径ρ<sub>minsub> D、滚子半径r<sub>rsub>不受任何限制
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、υ<sub>rsub>=Lω<sub>rsub>,方向沿AM B、υ<sub>rsub>=r(ω<sub>rsub>-ω),方向垂直AM,指向左下方 C、υ<sub>rsub>=r(L<sub>2sub>+r<sub>2sub>)1/2ω<sub>rsub>,方向垂直OM,指向右下方 D、υ<sub>rsub>=rω<sub>rsub>,方向垂直AM,指向在左下方
A、R<sub>1sub>烧坏,R<sub>2sub>不会烧坏 B、R<sub>1sub>、R<sub>2sub>均烧坏 C、R<sub>1sub>未烧坏,R<sub>2sub>烧坏 D、R<sub>1sub>、R<sub>2sub>均未烧坏
A、(R<sub>1sub>+R<sub>2sub>)/R<sub>1sub>R<sub>2sub> B、R<sub>1sub>R<sub>2sub>/(R<sub>1sub>+R<sub>2sub>) C、R<sub>1sub>+R<sub>2sub> D、R<sub>1sub>R<sub>2sub>
A、R<sub>1sub>烧坏,R<sub>2sub>不会烧坏 B、R<sub>1sub>,R<sub>2sub>均烧坏 C、R<sub>1sub>未烧坏,R<sub>2sub>烧坏 D、R<sub>1sub>,R<sub>2sub>均未烧坏
A、无源真空中,已知时变电磁场的磁场强度为H(r,t);rc="https://img.ppkao.com/2019-05/wangjing/201905151515598406.jpg" />,其中A<sub>1sub>、A<sub>2sub>为常数,求位移电流密度J<sub>dsub>
A、B<sub>Rsub>=2B<sub>rsub> B、B<sub>Rsub>=B<sub>rsub> C、2B<sub>Rsub>=B<sub>rsub> D、B<sub>Rsub>=4B<sub>rsub>