Question

Fig. shows common–emitter characteristic curve of a transistor. For V_CE = 10 V; I_B = 30 μ A; the current gain β_AC and α is

(1) 150; 1 

(2) 100; 0.99

(3) 150; 0.993 

(4) 150; 1.01

Answer 1

Correct option: (3) 150; 0.993

Explanation: 

The current gain; β_AC in common emitter configuration is

For V_CE = 10 V, I_B = 30 µA; the point on characteristics curve is P. Consider two points P and Q as shown in Fig. For V_CE = 10 V