Question

初二物理；电源电压不变R消耗的功率是P串联一电阻R'消耗功率P',P：P‘=36：5,且R大于R’那么R：R‘=?

Answer 1

根据I=U/R,可求得I1/I2=(R+R')/R,根据P=I^2R,P/P'=(R+R')^2R/R^2R'=36/5,化简得

(R-5R')(5R-R')=0,根据R大于R’,所以R：R’=5:1.