Relation Between Current Amplification Factors Alpha And Beta

Relation Between Current Amplification Factors Alpha And Beta — the NEET Physics formula with its derivation, variables, validity constraints and worked solver.

Relation between Current Amplification Factors (Alpha and Beta) Applicable to Bipolar Junction Transistors (BJTs) regardless of the specific biasing circuit, derived from the fundamental current relationship. Recall the fundamental relationship of transistor currents: I E = I C + I B Divide the equation by I C: I E/I C = 1 + I B/I C Substitute the definitions of the gains: = I C/I E and = I C/I B The equation becomes 1/ = 1 + 1/ Rearrange to solve for 1/ : 1/ = 1/ - 1 = (1 - )/ Invert both sides to isolate : = / (1 - ) Alpha ( ) must be strictly less than 1. Assumes leakage currents (I CBO) are negligible or included in the definition for large signal DC gain. Confusing (Common Base) with (Common Emitter). Thinking can be greater than 1 (it implies I C > I E which is impossible). Assuming is a fixed constant (it varies slightly with temperature and collector current).