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Electromagnetic Waves

Electromagnetic Waves in Everyday Technology

Description

Electromagnetic waves are grouped by wavelength and frequency. This set of waves is called the electromagnetic spectrum. It includes radio waves, microwaves, infrared, visible light, X-rays, and gamma rays.

Radio waves have wavelengths from millimeters to kilometers. They are often used for audio...

Transcript

电磁波谱是电磁波按照其波长或频率分布的图谱。它包括无线电波、微波、红外辐射、可见光、紫外线、X射线和伽马射线。

无线电波在电磁谱中具有最长的波长,范围从毫米到千米。它们由加速运动的电荷产生,可作为传输信息的载体。

微波炉产生微波,使食物加热。

加热的表面会发射红外辐射。遥控器使用波长约为 0.9 微米的红外辐射。

白炽灯发出的可见光辐射波长范围为0.4至0.7微米。

波长约为 0.35 微米的紫外线用于杀灭昆虫。

高频X射线的来源是原子内部的跃迁。波长约为1 × 10-4 微米的X射线用于骨骼扫描。

伽马射线在核衰变过程中被释放。放射治疗利用伽马射线。

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