In what direction does an electromagnetic wave travel?
The correct answer is D: It travels at a right angle to the electric and magnetic fields. In what direction does an electromagnetic wave travel is that it travels at a right angle to the electric and magnetic fields. Electromagnetic waves propagate perpendicular to both the E and H fields. For amateur radio operators, this is fundamental electromagnetic theory. Understanding this helps when working with antennas and propagation.
Exam Tip
EM wave direction = travels at right angle to electric and magnetic fields. Think 'E'lectromagnetic 'W'ave = 'E'lectric and 'M'agnetic fields, 'W'ave travels 'P'erpendicular. EM waves propagate perpendicular to both the E and H fields. Not phase angle, not parallel - just perpendicular.
Memory Aid
"EM wave direction = travels at right angle to electric and magnetic fields. Think 'E'lectromagnetic 'W'ave = 'P'erpendicular. EM waves propagate perpendicular to both the E and H fields. Fundamental electromagnetic theory."
Real-World Application
An electromagnetic wave: The electric field (E) and magnetic field (H) are perpendicular to each other, and the wave travels at a right angle (perpendicular) to both fields. This is fundamental electromagnetic theory - the wave propagation direction is perpendicular to both field vectors. This is the direction - at a right angle to both fields.
Key Concepts
Why Other Options Are Wrong
Option A: Incorrect. Direction doesn't depend on phase angle of magnetic field - EM waves travel perpendicular to both fields. Phase angle isn't the factor.
Option B: Incorrect. EM waves don't travel parallel to the fields - they travel perpendicular to both fields. Parallel is wrong.
Option C: Incorrect. Direction doesn't depend on phase angle of electric field - EM waves travel perpendicular to both fields. Phase angle isn't the factor.
题目解析
The correct answer is D: It travels at a right angle to the electric and magnetic fields. In what direction does an electromagnetic wave travel is that it travels at a right angle to the electric and magnetic fields. Electromagnetic waves propagate perpendicular to both the E and H fields. For amateur radio operators, this is fundamental electromagnetic theory. Understanding this helps when working with antennas and propagation.
考试技巧
EM wave direction = travels at right angle to electric and magnetic fields. Think 'E'lectromagnetic 'W'ave = 'E'lectric and 'M'agnetic fields, 'W'ave travels 'P'erpendicular. EM waves propagate perpendicular to both the E and H fields. Not phase angle, not parallel - just perpendicular.
记忆口诀
EM wave direction = travels at right angle to electric and magnetic fields. Think 'E'lectromagnetic 'W'ave = 'P'erpendicular. EM waves propagate perpendicular to both the E and H fields. Fundamental electromagnetic theory.
实际应用示例
An electromagnetic wave: The electric field (E) and magnetic field (H) are perpendicular to each other, and the wave travels at a right angle (perpendicular) to both fields. This is fundamental electromagnetic theory - the wave propagation direction is perpendicular to both field vectors. This is the direction - at a right angle to both fields.
错误选项分析
Option A: Incorrect. Direction doesn't depend on phase angle of magnetic field - EM waves travel perpendicular to both fields. Phase angle isn't the factor. Option B: Incorrect. EM waves don't travel parallel to the fields - they travel perpendicular to both fields. Parallel is wrong. Option C: Incorrect. Direction doesn't depend on phase angle of electric field - EM waves travel perpendicular to both fields. Phase angle isn't the factor.
知识点
Electromagnetic wave, Travel direction, Right angle, Electric and magnetic fields
Verified Content
Question from official FCC Extra Class question pool. Explanation reviewed by licensed amateur radio operators.