If an emitter current is changed by 4 mA , the collector current changes by 3 . 5 mA . The value of β will be:

Step-by-step solution

I ε = I C + I B ⇒ Δ I ε = Δ I C + Δ I B 4   mA = 3 . 5   mA + Δ I B ⇒ Δ I B = 0 . 5   mA ⇒ β = Δ I C Δ I B β = 3 . 5 0 . 5 ⇒ β = 7