章节大纲

  • A human hand surrounded by a blue electric field representing an electric phenomenon.

    Halt! This science fiction image shows a human hand surrounded by a green force field. It’s supposed to represent an electric field generated by a hand. What is an electric field? Read on to find out.    
    ::停止! 科幻小说图像显示, 人类手被绿力场包围。 它应该代表由一只手产生的电场。 什么是电场? 阅读以了解。

    What Is an Electric Field?
    ::什么是电场?

    An electric field is a space around a charged particle where the particle exerts electric force on other charged particles. Because of their force fields, charged particles can exert force on each other without actually touching. Electric fields are generally represented by arrows, as you can see in the Figure . The arrows show the direction of electric force around a positive particle and a negative particle. The field lines point away from a positive charge, and towards a negative charge.
    ::电场是一个充电粒子周围的空间,粒子在那里对其他充电粒子施加电力。由于其功率场,充电粒子可以在不实际触碰的情况下相互施压。电场通常由箭头代表,如图所示。箭头显示的是正向粒子和负向粒子周围的电力方向。外线指向正向粒子和负向充电。外线指向负向。

    Illustration displaying electric field lines around positive and negative charged particles.

    Watch the video below to learn move about how the strength of the electric field is related to the amount of charge  creating the field:
    ::了解电场的强度与创造电场的电量有何关联:

     

     

    Interacting Electric Fields
    ::互动电电场

    When charged particles are close enough to exert force on each other, their electric fields interact. This is illustrated in the Figure . The lines of force bend together when particles with different charges attract each other. The lines bend apart when particles with like charges repel each other. 
    ::当充电粒子靠近足以对彼此施压时,它们的电场相互作用。图中说明了这一点。当有不同电荷的粒子相互吸引时,强度线会弯曲。当有类似电磁的粒子互相反射时,强度线会弯曲。

    Electric field lines showing attraction between positive and negative charges.
    Note: +q = positive charge and –q = negative charge

    Q: What would the lines of force look like around two negative particles?
    ::问:两种负粒子的威力线是什么样子?

    A: They would look like the lines around two positive particles, except the arrows would point toward, rather than away from, the negative particles.
    ::A:它们看起来像两个正粒子周围的线条, 除了箭头指向负粒子而不是距离负粒子。

    Launch the Hockey simulation below and try to use the electric field to help you score a goal:
    ::在下面启动曲棍球模拟, 并尝试使用电场来帮助您得分 :

     

     

    Summary
    ::摘要

    • An electric field is a space surrounding a charged particle where the particle exerts electric force.
      ::电场是颗粒施加电力的带电粒子周围的空间。
    • When charged particles are close enough to exert force on each other, their electric fields interact. Particles with opposite charges attract each other. Particles with like charges repel each other. 
      ::当充电粒子距离足够近足以对彼此施压时,它们的电场就会相互作用。 带有相反电荷的粒子会相互吸引。 具有类似电荷的粒子会互相击退。

    Review
    ::回顾

    1. What is an electric field?
      ::什么是电场?
    2. Create a sketch showing how the electric fields of two negatively charged particles interact.
      ::创建一张草图, 显示两个负电荷粒子的电场是如何互动的 。