How is long distance radio communication usually affected by the charged particles that reach Earth from solar coronal holes?
The correct answer is B: HF communication is disturbed. How long-distance radio communication is usually affected by charged particles from solar coronal holes is that HF communication is disturbed. Coronal holes allow high-speed solar wind to escape, which can cause geomagnetic disturbances that disrupt HF propagation. For amateur radio operators, this means poor HF conditions when coronal holes are active. Understanding this helps explain coronal hole effects.
Exam Tip
Coronal holes effect = HF communication is disturbed. Think 'C'oronal 'H'oles = 'C'ause 'H'F disturbance. Charged particles from coronal holes cause geomagnetic disturbances that disrupt HF propagation. Not improvement, not VHF/UHF - just HF disturbance.
Memory Aid
"Coronal holes effect = HF communication is disturbed. Think 'C'oronal 'H'oles = 'C'ause 'H'F disturbance. Charged particles from coronal holes cause geomagnetic disturbances that disrupt HF propagation. Key effect of coronal holes."
Real-World Application
A coronal hole on the Sun allows high-speed solar wind to escape. When this reaches Earth, it causes geomagnetic disturbances that disrupt HF propagation. HF communication becomes difficult or impossible, especially at high latitudes. The disturbance typically lasts for days as the coronal hole rotates across the Sun.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Coronal holes don't improve HF communication - they disturb it. The high-speed solar wind from coronal holes causes geomagnetic disturbances.
Option C: Incorrect. Coronal holes don't improve VHF/UHF ducting - they affect HF propagation, not VHF/UHF ducting. Ducting is a different phenomenon.
Option D: Incorrect. Coronal holes don't disturb VHF/UHF ducting - they affect HF propagation, not VHF/UHF. The effect is on HF, not VHF/UHF.
题目解析
The correct answer is B: HF communication is disturbed. How long-distance radio communication is usually affected by charged particles from solar coronal holes is that HF communication is disturbed. Coronal holes allow high-speed solar wind to escape, which can cause geomagnetic disturbances that disrupt HF propagation. For amateur radio operators, this means poor HF conditions when coronal holes are active. Understanding this helps explain coronal hole effects.
考试技巧
Coronal holes effect = HF communication is disturbed. Think 'C'oronal 'H'oles = 'C'ause 'H'F disturbance. Charged particles from coronal holes cause geomagnetic disturbances that disrupt HF propagation. Not improvement, not VHF/UHF - just HF disturbance.
记忆口诀
Coronal holes effect = HF communication is disturbed. Think 'C'oronal 'H'oles = 'C'ause 'H'F disturbance. Charged particles from coronal holes cause geomagnetic disturbances that disrupt HF propagation. Key effect of coronal holes.
实际应用示例
A coronal hole on the Sun allows high-speed solar wind to escape. When this reaches Earth, it causes geomagnetic disturbances that disrupt HF propagation. HF communication becomes difficult or impossible, especially at high latitudes. The disturbance typically lasts for days as the coronal hole rotates across the Sun.
错误选项分析
Option A: Incorrect. Coronal holes don't improve HF communication - they disturb it. The high-speed solar wind from coronal holes causes geomagnetic disturbances. Option C: Incorrect. Coronal holes don't improve VHF/UHF ducting - they affect HF propagation, not VHF/UHF ducting. Ducting is a different phenomenon. Option D: Incorrect. Coronal holes don't disturb VHF/UHF ducting - they affect HF propagation, not VHF/UHF. The effect is on HF, not VHF/UHF.
知识点
Coronal holes, Charged particles, HF communication, Propagation disturbance
Verified Content
Question from official FCC General Class question pool. Explanation reviewed by licensed amateur radio operators.