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For a transistor connected in common-base mode, the collector current is 5.488 mA when the emitter current is 5.60 mA. What is the value of the base current amplification factor (β)?

Correct answer: 49

Solution

alpha = Ic/Ie = 5.488/5.60 = 0.98. The current amplification factor beta = alpha/(1 - alpha) = 0.98/0.02 = 49.

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