So these end up cancelling out essentially.

所以这些最终基本上抵消了。

A classic example of forces and torques cancelling each other out, is a ladder leaning against a wall.

褪色的经典例子 权力，是搁在墙上的梯子。

And when a wave is out of phase by 180 degrees, it's destructive, with the crests and troughs cancelling each other out.

当波相位相差 180 度时，它具有破坏性，波峰和波谷相互抵消。

When the two are brought together using the group's addition operation, they result in the identity element, zero, so they can be thought of as cancelling each other out.

当使用群的加法运算将两者放在一起时，它们的单位元为零，因此可以认为它们相互抵消了。

After cancelling out like terms, you're left with an equation that tells you how much energy you have per unit area based on the strength of the electric field, which you can also replace with the magnetic field magnitude.

取消这些项后，您现在有了一个方程式，该方程式根据电场的强度告诉您每单位面积有多少能量，您也可以用磁场的大小代替。