Definition check for BJT current gain parameters: Evaluate the statement: “The beta (β) of a BJT is the ratio of collector current to emitter current.” Select the best assessment.

Introduction / Context:
Accurate definitions of transistor parameters are vital when reading datasheets and designing bias networks. Two common current gain parameters are alpha (α) and beta (β), and mixing them up causes calculation errors and bias misinterpretation.

Given Data / Assumptions:

• BJT operated in forward-active mode.
• Currents IE (emitter), IC (collector), and IB (base) satisfy IE = IC + IB.

Concept / Approach:
By definition: β = IC/IB (common-emitter current gain). Alpha is defined as α = IC/IE (common-base current gain). Since IB is typically much smaller than IC, β is usually large, while α is close to 1. The statement confuses β with α.

Step-by-Step Solution:

Verification / Alternative check:
Using IE = IC + IB, one can show β = α/(1 − α) and α = β/(β + 1), confirming the distinct meanings of α and β.

Why Other Options Are Wrong:

• Correct / true only for saturation / germanium-only / temperature-only: None change the formal definitions; β is never defined as IC/IE.

Common Pitfalls:
Memorizing formulas without variable context; confusing device-mode effects with parameter definitions.

Final Answer:
Incorrect