近代科学研究的电磁波,是由許多不同的成分構成的。其中波長較长的是无线电波,其次是紅外线、可見光线和紫外线,波長比较短的是X射綫和γ射线等。 無线电波是波長最長的电磁波,它是由于电子的振蕩而产生的。无线电波最初应用在通訊上,它能够超越空间,穿过高山、森林、沙漠和海洋,把信号傳送到很远的地方。由于大气中电离层的反射和散射,无线电波可以超越地球表面的曲度,傳播到地球上任何地方。根据無线电原理建立起来的無线电报、無线电話、無线电广播、無线电传真、电视和雷达,可以把声音、文字和形象傳送到遙远的地方,或用来探测远处物体的位置和距离,在現代工業建設、国防和文化教育事業中获得了广泛的应用。红外线的波長是在無线电波和可見光线之間。红外线一般是从炽热的物体上發射出来的。当物体的温度升高的时候,除了能够发出可見光线以外,同时也常常發射出大量的看不見的 The electromagnetic wave of modern scientific research is composed of many different components. Longer wavelengths are radio waves, followed by infrared rays, visible rays, and ultraviolet rays. X-rays and gamma rays are relatively short wavelengths. Radio waves are the longest wavelength electromagnetic waves, which are generated by the oscillation of electrons. Initially applied to communications, radio waves can transcend space, travel through mountains, forests, deserts, and oceans, sending signals far away. Due to the reflection and scattering of the ionosphere in the atmosphere, radio waves can propagate beyond the curvature of the Earth’s surface to any place on Earth. Radiotelegraphs, radiotelephones, radio broadcasts, radio facsimiles, televisions, and radars built on radio principles can transmit sound, text, and images to remote locations or to detect distant The location and distance of objects are widely used in modern industrial construction, national defense, and culture and education. The wavelength of infrared rays is between radio waves and visible rays. Infrared is usually emitted from a hot object. When the temperature of an object rises, in addition to emitting visible light, it often emits a large amount of invisible light.