The two transistor in fig. below are identical. If β =

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The two transistor in fig. below are identical. If β = 25, the current I_C2 is:

1. 28 µA
2. 23.2 µA
3. 26 µA
4. 24 µA

Correct Option: B

Since both the transistor are identical, and both the transistor are in the forward active region.
I_B₁ + I_B₂ + I_C₁ = 25 mA ....(i)
VBE is same for both the transistor since both are identical
i.e. I_C₁ = I_C₂ and
I_B₁ = I_B₂
so, equation reduces
2I_B₁ + I_C₁ = 25 µA
or 2I_B₁ + I_B₁ . β = 25 µA
or I_B₁ (β + 2) = 25 µA

or I_B₁ =	25	= I_B₂
	β + 2

or I_C₂ = β. I_B₂ = β.	25
	β + 2

= 25.	25	= 23.2 µA
	(25 + 2)

Hence alternative (B) is the correct choice.