Question:

In a BJT, largest current flow occurs

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BJT Current Relationship. $I_E = I_B + I_C$. Typically $I_C \gg I_B$. Therefore, $I_E$ is the largest current, and $I_B$ is the smallest.

Updated On: May 6, 2025

In the emitter
In the collector
In the base
Through CB junction.

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The Correct Option is A

Solution and Explanation

For a Bipolar Junction Transistor (BJT) operating in its active region, Kirchhoff's Current Law dictates that the emitter current ($I_E$) is the sum of the base current ($I_B$) and the collector current ($I_C$): $$ I_E = I_B + I_C $$ The base is very thin and lightly doped, so the base current $I_B$ (required to control the transistor) is much smaller than the collector current $I_C$ (the main output current)
Typical current gain $\beta = I_C / I_B$ is large (e
g
, 50-500)
Since $I_C$ is typically much larger than $I_B$, their sum, $I_E$, is always the largest of the three terminal currents
Current flows *through* junctions, but the largest *terminal* current is the emitter current

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