transmitter appear to transfer energy continuously. This view
is useful to a certain extent (radiation of low frequency), but
problems are found at high frequencies (see ultraviolet
the Lorentz force law.
电荷和电流与电磁场相互作用 的方式由麦克斯韦方程组和洛 伦兹力定律所描述。
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ห้องสมุดไป่ตู้ 3
From a classical point of view, the electromagnetic field can be regarded as a smooth, continuous field, propagated in a wavelike manner, whereas from a quantum mechanical point of view, the field can be viewed as being composed of photons.
Electromagnetic Field
New Words
vicinity 邻近，附近 charge 电荷 photon 光子 atom 原子 catastrophe 大灾难，大祸 emission 发射，散发 incident 入射的 electrodynamics 电动力学 gravitational 重力的
电磁场在空间无限延伸， 并描述电磁相互作用。
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The field can be viewed as the combination of an electric field
and a magnetic field. The electric field is produced by
stationary charges, and the magnetic field by moving charges
信息科学与电子工程专业英语
Technical English
For Information Science and Electronic Engineering
信息科学与电子工程专业英语
Unit 3
EM Fields, Antenna and Microwaves
信息科学与电子工程专业英语
Part I
catastrophe). This problem leads to another view.
The ultraviolet catastrophe, also called the Rayleigh-Jeans catastrophe, was a prediction of early 20th century classical physics that an ideal black body at thermal equilibrium will emit radiation with infinite power.
从经典的角度，电磁场可认为是光滑、连 续的场，以波动方式传播；而从量子力学 的角度，场可看作是由光子组成的。
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4 Structure of the electromagnetic field
The electromagnetic field may be viewed in two distinct ways. Continuous structure: Classically, electric and magnetic fields are thought of as being produced by smooth motions of charged objects. For example, oscillating charges produce electric and magnetic fields that may be viewed in a “smooth”, continuous, wavelike manner.
stationary 静止的，不变的 quantum 量子 oscillate 振荡 ultraviolet 紫外线的 photoelectric effect 光电效应 metallic 金属的 eject 喷射，强制离开 dynamics 动力学 entity 实体
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The electromagnetic field is a physical field produced by electrically charged objects. It affects the behavior of charged objects in the vicinity of the field. The electromagnetic field extends indefinitely throughout space and describes the electromagnetic interaction. It is one of the four fundamental forces in the nature (the others are gravitation, the weak interaction, and the strong interaction)
(currents); these two are often described as the sources of the
field. The way in which charges and currents interact with the
electromagnetic field is described by Maxwell’s equations and
例如，振荡电荷产生电场和磁场，可 看成平滑的、连续的波动方式。
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In this case, energy is viewed as being transferred
continuously through the electromagnetic field between any
two locations. For instance, the metal atoms in a radio