# In a transistor if increase in emitter current is 4 mA and corresponding increase in collector

In a transistor if increase in emitter current is 4 mA and corresponding increase in collector current is 3.5 mA. Find $$\beta$$

a] .875

b] .5

c] 7

d]1

verified

$$\triangle I_E=4$$

$$\\ \\ \\ \triangle I_c=3.5$$

$$\ \\\alpha={\triangle I_c \over \triangle I_E} ={ 3.5\over4}={7\over8} \\ \\$$

$$\beta={ \alpha\over1-\alpha}={{7\over8}\over 1- {7\over8}}=7$$

Hence , option {C} is correct

7