t≥T l!(+)=2()=-1003(-)+50=-100×0.5e+50=316 i(℃) 20+(G+ 0=-0516A l2(c+)=-20-(7+)=-516 y=0g=0c=RC=100950×100=006 =n+[c)-a)]e 0.516·e 200-0.005) 闪四 西南交通大学西南交通大学 t ³ t uc ( ) uc ( ) 100i c ( ) 50 100 0.5e 50 31.6V 1 = = - + = - ´ + = - + - - t t t A u i c c 0.516 100 20 ( ) ( ) = - + = - + + t t uR (t + ) = -20 - uc (t + ) = -51.6V i cp = 0 uRp = 0 RC 100 50 10 0.005s 6 = = ´ ´ = - t [ ] ( ) 1 ( ) ( ) t t t t - - + + \ = + - × t c cp c cp i i i i e e A 200(t 0.005) 0.516 - - = - ×