We don't know what the force is, because we are hoping to say force is going to be m times a.

我们不知道力有多大,因为我们希望力是 m 和 a 的乘积

耶鲁公开课 - 基础物理课程节选

Then we may, from this equation, say a certain force is acting in a given situation by multiplying the m times the a.

然后根据这个方程,我们就能说,得到给定条件下的作用力,它等于 m 和 a 的乘积

耶鲁公开课 - 基础物理课程节选