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äºæ管æ£ååéå0.7Vã
设çµé»R1åR2ï¼R1åäºæ管串èï¼å¹¶èæ½å çµå为Vã
1ãæ±R1ãäºæ管æ¯è·¯çµæµ
I1 = ï¼V - 0.7 ï¼/ R1
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I2 = V / R2
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I = I1 + I2 =ï¼V -0.7ï¼/R1 + V / R2 = (VR2 - 0.7R2 + VR1 ) / R1 R2
æ»çµé» = V / I = R1 * R2 * V /ï¼VR1+ VR2 -0.7R2ï¼