主要区别-重力与电磁

引力和电磁力是物理学中四种基本力中的两种。在四种基本力量中，这两种最为我们所熟悉。重力和电磁的主要区别在于重力是质量之间的力，而电磁是电荷之间的力。

什么是重力(gravity)？

Gravity refers to the force of attraction between masses. It is one of the four fundamental forces, resp***ible for objects on Earth always falling down, for The Moon’s motion around The Earth, and The Earth’s motion around The Sun. It was Sir Isaac Newton who first managed to describe gravity mathematically when he realized that the motion of an apple falling from a tree and the motion of The Moon around The Earth are both due to an attraction between those objects and The Earth. His law of gravitation states that if two objects having masses  and  are separated by a distance  , the gravitational attraction between them is given by:

Where  is the universal gravitational c***tant  . Later, Einstein’s work showed that Newton’s theory of gravity was incomplete. Today, gravity is explained using Einstein’s theory of general relativity. In Einstein’s theory, gravity is described as a curvature of space-time.

In general relativity, gravity is thought to be a result of warped space-time around massive objects.

在四种基本力中，重力是最难与其他三种力统一的力。与其他三种类型（强力、弱力和电磁）相比，它也相对较弱。

什么是电磁学(electromagneti**)？

Electromagneti** is the force that exists between charges. Electrostatic forces may exist between charges which are at rest, and when charges move, they may create magnetic fields around themselves. So, moving charges may exert electrostatic forces as well as magnetic forces between each other. If a particle with a charge is moving with a velocity  through a region that has an electric field with strength  and a magnetic field with strength  , then the force  on the particle is given by:

电磁学负责电和磁铁之间的吸引力。在一个微妙的层面上，它还负责让你坐在椅子上，而不会摔倒。在粒子物理学的标准模型下，电磁学被描述为由光子粒子介导的。

重力(gravity)和电磁学(electromagneti**)的区别

他们的行动

重力作用于质量。

电磁作用于电荷。

相对强度

电磁力大约是重力的1035倍[1]。

相互作用的性质

地心引力总是吸引人的。

电磁可以是吸引的，也可以是排斥的。

屏蔽能力

屏蔽空间免受电磁力的影响是可能的。

没有办法保护空间不受引力的影响。

参考文献：

1. 休斯，S(2005年2月1日）。介绍；库伦定律；叠加；电能。2015年11月3日检索自麻省理工学院

Image Courtesy:

“Illustration of spacetime curvature.” by User:Johnstone (Created using an image of planet earth from NASA’s Galileo spacecraft.) [CC BY-SA 3.0], via Wikimedia Comm***