S闭合神明仔时I=P2/U2=10W/U2=10W/(U-5V),R1=U1/I=5V/【10W/(U-5V)】=(U-5)/2S断开时R1=U/游汪I=U/3V两式联立:(U-5)/2=R1=U/3,解得U=15V这样R1=U/I=15V/3V=5Ω又U/(R1+R2)=I=10W/(U-5V)转槐尘化成:15/(5+R2)=10/(15-5)解得R2=10Ω所以U=15V,R1=5Ω,R2=10Ω