(b)求内阻R a o- 5U1 52 加压求流 62 R→ b0— U1+ 22 a 5U1 42 5Uj+810+U=Uo 42 U=210 U1+ R=U/I0=202 b 22Ri (b) 求内阻Ri 加压求流 5U1+8I0+U1 =U0 U1=2I0 Ri =U0 /I0=20 a b 2 4 6 6 6 5U1 + – – U1 + 2 4 4 5U1 a b U0 I0 + – – U1 + + –