🔍 Key Concepts

• Q (quality factor) of an inductor and what affects it • How core materials (like iron) change the behavior of inductors compared with air-core inductors • Relationship between selectivity, gain, and Q in tuned circuits

💭 Think About

• How does adding an iron core affect the inductance value and losses in a coil compared to an air core? • In a tuned circuit, what does a higher Q do to the bandwidth and selectivity of the circuit? • Does changing the inductor’s core material by itself directly increase amplifier gain, or does it mainly change reactive properties like inductance and Q?

✅ Before You Answer

• Be clear on the definition of Q (quality factor) and how it relates to bandwidth and selectivity. • Decide whether iron cores tend to increase or decrease losses in real coils at the frequencies in question. • Ask whether gain is an inherent property of an inductor, or of the active circuit elements (like transistors or tubes).