A.电流表A1:挡位1(0~3A,内阻约0.05Ω),挡位2(0~0.6A,内阻约0.2Ω)
B.电流表A2:0-300μA,内阻rA=100Ω
C.定值电阻:R0=2Ω,R1=900Ω,R2=4900Ω
D.滑动变阻器:R3(0—5Ω,2A),R4(0~15Ω,1A)
E.开关一只、导线若干