which is dimensionless, we call that strain.

它是无量纲的，我们称之为拉力。

Dimensionless quantities in physics are those that require no unit .

物理学中无量纲的量就是不需要单位的量。

This is a dimensionless number because it's length divided by length.

这儿没有量纲，因为是长度除以长度。

D index is also called formation drillability index (dimensionless).

指数也称地层可钻性指数(无量钢)。

The physical meaning of dimensionless numbers cannot usually be formulated clearly.

无因次数的物体意义一般不能清楚地用公式表达。