Which type of core material decreases inductance when inserted into a coil?
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.
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 Application
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.
Key Concepts
Why Other Options 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.
题目解析
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.
考试技巧
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.
记忆口诀
Core material that decreases inductance = brass. Think 'B'rass = 'D'ecreases inductance. Brass is non-magnetic and actually reduces inductance. Important for component knowledge.
实际应用示例
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.
错误选项分析
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.
知识点
Core material, Decreases inductance, Inserted into coil, Brass
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.