🔍 Key Concepts
• Impedance vs resistance for AC and DC in an inductor
• What a choke coil is used for in radio or power circuits
• Meaning of high Q in RF (radio frequency) coils
💭 Think About
• Think about how an inductor behaves for DC current versus AC current—does it block one more than the other?
• Why would a designer choose a choke coil in an RF or power supply filter? What properties are they taking advantage of?
• If a coil has a high Q (low losses), how does that relate to its effectiveness in passing or rejecting certain kinds of currents?
✅ Before You Answer
• Be clear on the difference between impedance to AC and resistance to DC in an inductor.
• Recall that Q (quality factor) describes how lossy (or efficient) a resonant coil is at RF.
• Verify whether a practical choke coil is expected to have all of the listed properties or only some of them.