So, a massless body cannot have a net force on it, because the acceleration of the rope cannot be infinite.

所以没有质量的物体不会受到力,因为绳子的加速度不可能是无穷大

耶鲁公开课 - 基础物理课程节选

You will learn in 8.02 that if you have a charged body changing direction, that constitutes an acceleration.

你们将在8。02中学到,如果一个带电体改变方向时，产生一个加速度。

麻省理工公开课 - 固态化学导论课程节选

It says that, "If a body has an acceleration, then you need a force and the relation of the force to acceleration is this thing."

它是这么说的,"如果一个物体有加速度,那么你需要有一个力,力和加速度的关系是这样的"

耶鲁公开课 - 基础物理课程节选

First one says, if you knew the force acting on any body, without going into what caused the force, then you may set that force equal the mass times acceleration of the body.

第一部分是,如果你知道作用在任一物体上的力,无论这个力的来源是什么,都可以令力等于质量乘以物体的加速度

耶鲁公开课 - 基础物理课程节选

We can be precise about how much bigger by saying, "If the acceleration of a body to a given force is ten times that of a one kilogram mass, then this mass is one-tenth of one kilogram."

我们能精确地知道质量能大多少,只需要说,"如果物体在给定力作用下的加速度,是一个 1 千克物体的加速度的 10 倍,那这个物体的质量就是 1 千克的十分之一"

耶鲁公开课 - 基础物理课程节选

Then, in every situation where the body has an acceleration a, the location has to have this form, where this number is where it was initially, this was the initial velocity of the object.

在任何研究对象具有加速度a的情况下,它的位移就一定具有这种形式,这个系数代表了它的初位移,这个代表了它的初速度

耶鲁公开课 - 基础物理课程节选