Physics · Semiconductors, semiconductor diode: I-V characteristics in forward and reverse bias, diode as a rectifier

In common base circuit of a transistor, current amplification factor is 0.95 Cal

In common base circuit of a transistor, current amplification factor is 0.95 Calculate the emitter current if base current is \( 0.2 \mathrm{mA} \)

  • A. \( 2 \mathrm{mA} \)
  • B. \( 4 \mathrm{m} \)
  • C. 6 m A \)
  • D. \( 8 \mathrm{m} \)

Step-by-step solution

In a common base transistor, current amplification factor α = I_C / I_E. Also, I_E = I_B + I_C. Substituting I_C = α I_E gives I_E = I_B + α I_E, so I_E (1 - α) = I_B, hence I_E = I_B / (1 - α) = 0.2 mA / (1 - 0.95) = 0.2 / 0.05 = 4 mA.
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