F(P,Kx,c,U)=P*Kx/(U*c)
F(5,1,0.8,0.22)

'Ҫϵ() (A)
P=5        'ܹ(KW)
Kx=1      'Ҫϵ
c=0.8       '
U=0.22      'ѹ(KV)