例题 例:如图示当K闭合时i1=?U1= 3鸟 解:换路前:t=0 6 的aal (0-) ×2=1.5A 6+2 象 换路后:t=0 1(0)=i1(0)=15AR 6×3 2=40 6+3 2(S) R 4 hBL U,(t=L 1.5×4e2=6e2例题 ⚫ 例：如图示当K闭合时iL =？UL =？ 解：换路前：t=0- 2 1.5A 6 2 6 i (0-) L  = + = 换路后：t=0+ ( ) ( ) + =  +  + = − = = 2 4 6 3 6 3 i L 0 i L 0 1.5A R 2(S) 4 8 R L  = = = i (t) i ( )e e (A) t t L L   − − = 0+ =1.5 2 2 ( ) 1.5 4 6 t t L L e e dt di U t L − − = =  =