Question

电源,电阻箱R,定值电阻R1,形成串联电路,在R1上并联电压表,绘出1/U-R图象是一条直线斜率为K,

Answer 1

U/R1=E/(R+R1+r)

∴1/U=(1/R1E)*R+(R1+r)/(R1E)

∴K=1/R1E ①

B=(R1+r)/(R1E) ②

联立①②求解得:

E=1/(R1K)

r=B/K-R1