Which of the following materials has the highest temperature stability of its magnetic characteristics?
The correct answer is B: Powdered iron. Which of the following materials has the highest temperature stability of its magnetic characteristics is powdered iron. Powdered iron has better temperature stability than ferrite. For amateur radio operators, this is important for component knowledge. Understanding this helps when selecting core materials.
Exam Tip
Highest temperature stability of magnetic characteristics = powdered iron. Think 'P'owdered 'I'ron = 'P'redictable 'I'n all temperatures. Powdered iron has better temperature stability than ferrite. Not brass, not ferrite, not aluminum - just powdered iron.
Memory Aid
"Highest temperature stability of magnetic characteristics = powdered iron. Think 'P'owdered 'I'ron = 'T'emperature 'S'table. Powdered iron has better temperature stability than ferrite. Important for component knowledge."
Real-World Application
Materials with magnetic characteristics: Powdered iron has the highest temperature stability. Its magnetic properties change less with temperature compared to ferrite. This is the material - powdered iron has highest temperature stability.
Key Concepts
Why Other Options Are Wrong
Option A (Brass): Incorrect. Brass isn't a magnetic material - powdered iron has highest temperature stability. Brass isn't the material.
Option C (Ferrite): Incorrect. Ferrite doesn't have highest temperature stability - powdered iron does. Ferrite isn't the answer.
Option D (Aluminum): Incorrect. Aluminum isn't a magnetic material - powdered iron has highest temperature stability. Aluminum isn't the material.
题目解析
The correct answer is B: Powdered iron. Which of the following materials has the highest temperature stability of its magnetic characteristics is powdered iron. Powdered iron has better temperature stability than ferrite. For amateur radio operators, this is important for component knowledge. Understanding this helps when selecting core materials.
考试技巧
Highest temperature stability of magnetic characteristics = powdered iron. Think 'P'owdered 'I'ron = 'P'redictable 'I'n all temperatures. Powdered iron has better temperature stability than ferrite. Not brass, not ferrite, not aluminum - just powdered iron.
记忆口诀
Highest temperature stability of magnetic characteristics = powdered iron. Think 'P'owdered 'I'ron = 'T'emperature 'S'table. Powdered iron has better temperature stability than ferrite. Important for component knowledge.
实际应用示例
Materials with magnetic characteristics: Powdered iron has the highest temperature stability. Its magnetic properties change less with temperature compared to ferrite. This is the material - powdered iron has highest temperature stability.
错误选项分析
Option A (Brass): Incorrect. Brass isn't a magnetic material - powdered iron has highest temperature stability. Brass isn't the material. Option C (Ferrite): Incorrect. Ferrite doesn't have highest temperature stability - powdered iron does. Ferrite isn't the answer. Option D (Aluminum): Incorrect. Aluminum isn't a magnetic material - powdered iron has highest temperature stability. Aluminum isn't the material.
知识点
Materials, Highest temperature stability, Magnetic characteristics, Powdered iron
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.