By the 1890s, Nikola Tesla had demonstrated that not just magnetic fields but also electromagnetic waves themselves could transmit power-and over far greater distances.
到1890年，尼古拉·特斯拉论证出电磁波本身也能传输电能，并且和磁场相比传输距离要长得多。
Radiofrequency waves are electromagnetic fields, and unlike ionizing radiation such as X-rays or gamma rays, cannot break chemical bonds nor cause ionization in the human body.
射频波就是电磁场，但是与X射线或伽玛射线辐射等电离辐射不同的是，射频波不会打破化学键，也不会给人体造成电离辐射伤害。
Mobile phones use radio waves to send and receive calls and these produce small electromagnetic fields that can be absorbed by the head and brain.
手机利用无线电波接打电话，而且这些无线电波会产生能被人脑吸收的电磁场。
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