Electromagnetic Force
电磁力
There are several fundamental forces that hold our universe together.
有几种基本的力量将我们的宇宙维系在一起。
One of these, of course, is gravity, the force between objects that have mass.
其中之一，当然是重力，有质量的物体之间的力。
Another important force is the electromagnetic force.
另一个重要的力是电磁力。
The electromagnetic force is responsible for chemical reactions.
电磁力负责化学反应。
Without it there would be no atoms or molecules.
没有它就不会有原子或分子。
Up until a couple of hundred years ago, very little was known about this force.
直到几百年前，人们对这种力知之甚少。
Learning about the electromagnetic force and how to use it was a major step forward.
了解电磁力和如何使用它是一个重大的进步。
It revolutionized communication, transportation and manufacturing.
它彻底改变了通讯、运输和制造业。
Imagine what life would be like without electricity!
想象一下没有电的生活将是什么样子!
Learning about the electromagnetic force and how to use it was a major step forward.
了解电磁力和如何使用它是一个重大的进步。
Which of the fundamental forces is between objects that have mass?-Gravity.
有质量的物体之间的基本力是什么?-重力
The electromagnetic force has two parts, the electrical force and the magnetic force.
电磁力有两部分，电磁力和磁力。
The electric force is the force between electrically charged particles such as electrons and protons.
电力是带电粒子(如电子和质子)之间的力。
Electric charges attract or repel each other with a force that depends on the distance between them.
电荷相互吸引或排斥，其力取决于它们之间的距离。
The magnetic force is the force between magnetic poles, such as the north and south pole.
磁力是介于磁极之间的力，如北极和南极。
In fact, the Earth is like a large bar magnet, with a north and a south pole.
事实上，地球就像一个巨大的条形磁铁，有一个北极和一个南极。
Many animals use the Earth's magnetic field to navigate during their migrations.
许多动物在迁徙过程中利用地球磁场导航。
We can also see this magnetic field when we use a compass.
我们用指南针也可以看到这个磁场。
Why is the earth like a large bar magnet?- It has a north and a south pole.
为什么地球像一个大磁铁?它有一个北极和一个南极。
Many animals use the Earth's magnetic field to navigate during their migrations.
许多动物在迁徙过程中利用地球磁场导航。
For what purpose do many animals use the Earth's magnetic field?- for navigation
许多动物利用地球磁场有什么目的?——导航
Electrons and protons are examples of what?-electrically charged particles
电子和质子是什么例子?电带电粒子
Why does the Earth have a magnetic field?
为什么地球有磁场?
Many scientists believe that the Earth's magnetic field is due to the Earth's rotation.
许多科学家认为地球的磁场是由地球的自转引起的。
Deep inside the Earth is a solid iron core, surrounded by a liquid metal outer core.
地球的深处是一个固态铁核，外围是液态金属核。
The moving electric currents inside this liquid metal create a magnetic field.
流动的电流在液态金属内部产生磁场。
Deep inside the Earth is a solid iron core, surrounded by a liquid metal outer core. The moving electric currents inside this liquid metal create a magnetic field.
地球的深处是一个固态铁核，外围是液态金属核。流动的电流在液态金属内部产生磁场。
The Earth's magnetic field is important because it protects us from the solar wind.
地球磁场很重要，因为它保护我们不受太阳风的影响。
The solar wind is a current of charged particles coming at us from the Sun.
太阳风是来自太阳的带电粒子流。
When the solar wind nears the Earth, the Earth's magnetic field deflects it away.
当太阳风靠近地球时，地球磁场会使太阳风偏转。
This protects the Earth from the radiation, which can be dangerous to life.
这可以保护地球免受辐射，而辐射可能会危及生命。
It also protects the satellites that we use for communication.
它还保护了我们用来通信的卫星。
How does the magnetic field protect the Earth?-It deflects the solar wind away from the Earth.
磁场是如何保护地球的?它使太阳风偏离地球。
What protects the Earth from the solar wind?- The Earth's magnetic field
是什么保护地球不受太阳风的影响?-地球磁场
When the solar wind nears the Earth, the Earth's magnetic field deflects it away. This protects the Earth from the radiation ,which can be dangerous to life.
当太阳风靠近地球时，地球磁场会使太阳风偏转。这可以保护地球免受辐射，而辐射可能会危及生命。
