(Ni+N22)A2 H-A(a-x)+(a+为A =N,HA=。NAA+N) A(a-x)+(a+)A2 女=A=会奇哈 入1=L(X)5+M(X)52 2=M(x)1+L2(x)12 b肉=A阳岭8：与肉=AB产8：M网A。合8不 “AA2N22 =1(x)L2(x dw=i da+i dx2-fdx d(i+iz-w)=di +72 diz +f dx w'(co-energy) dw'=λ1di+2di2+fdx f=+0w' ox i,iconstant (x,,2) ③ ③ ① 6.641,Electromagnetic Fields,Forces,and Motion Lecture 13 Prof.Markus Zahn Page 10 of 146.641, Electromagnetic Fields, Forces, and Motion Lecture 13 Prof. Markus Zahn Page 10 of 14 ( ) ( )( ) 11 22 2 1 1 2 Ni Ni A H = A a x a xA + −++ ( ) ( )( ) 0 1 1 2 11 22 1 101 1 1 2 N A A Ni Ni =N H A = A a x a xA µ + λ µ −++ ( ) ( )( ) 0 2 1 2 11 22 2 202 2 1 2 N A A Ni Ni =N H A = A a x a xA µ + λ µ −++ () () λ + 111 2 =L x i M x i () () λ + 2 12 2 =M x i L x i ( ) ( )( ) ( ) ( )( ) ( ) ( )( ) 2 2 0 1 21 0 1 22 0 1 212 1 2 1 2 1 21 2 A A N A A N A A NN L x= ; L x= ; Mx= A a x a xA A a x a xA A a x a xA µ µµ −++ −++ −++ = L xL x 1 2 () () dw = i d i d f dx 112 2 λ+ λ− ( ) λ + λ − λ +λ + d i i w = di di f dx 11 22 1 1 2 2 w’ (co−energy) dw' = di di f dx 11 22 λ +λ + 1 2 i ,i cons tan t w' f = x ∂ + ∂