Deep Dive: E6D11
The correct answer is B: Brass. Which type of core material decreases inductance when inserted into a coil is brass. Brass is non-magnetic and actually reduces inductance. For amateur radio operators, this is important for component knowledge. Understanding this helps when selecting core materials.
Why Other Answers Are Wrong
Option A (Ceramic): Incorrect. Ceramic doesn't decrease inductance - brass does. Ceramic isn't the material. Option C (Ferrite): Incorrect. Ferrite increases inductance - brass decreases it. Ferrite isn't the material. Option D (Aluminum): Incorrect. Aluminum doesn't decrease inductance - brass does. Aluminum isn't the material.
Exam Tip
Core material that decreases inductance = brass. Think 'B'rass = 'B'ad for inductance (decreases). Brass is non-magnetic and actually reduces inductance. Not ceramic, not ferrite (increases), not aluminum - just brass.
Memory Aid
Core material that decreases inductance = brass. Think 'B'rass = 'D'ecreases inductance. Brass is non-magnetic and actually reduces inductance. Important for component knowledge.
Real-World Example
Core materials inserted into a coil: Brass decreases inductance when inserted. Brass is non-magnetic and has a permeability less than air, so it reduces the inductance. This is the material - brass decreases inductance.
Source & Coverage
Question Pool: 2024-2028 Question Pool
Subelement: E6D
Reference: 2024-2028 Question Pool · E6 - Circuit Components
Key Concepts
Verified Content
Question from the official FCC Extra Class pool. Explanation reviewed by licensed amateur radio operators and mapped to the E6D topic.