# What does this bar symbol mean in this equation?

I read a paper in which there is this equation:

$\bar v = \frac{v}{a}$

The variable $v$ is either a vector containing a relative velocity or its norm and $a$ is either a vector containing a relative acceleration or its norm. In the paper it is stated that vectors are to be shown in bold, while their norms are to be shown as standard text. However, considering the fact that I have only access to a low quality printed version of the paper, I'm unable to discern one from the other.

Now, I don't understand the meaning of this equation and what the bar symbol over the $v$ on the left side means.

• It looks like it means exactly what you've written. $\overline{v}$ stands for the division of $v$ by $a$. Does that make sense in the context of the paper? They probably just did it to save time. – The Count Jan 18 '17 at 14:28
• The dimension of $\dfrac{v}{a}$ is time, in general $$\frac{v}{a}=\frac{\frac{ds}{dt}}{\frac{dv}{dt}}=\frac{ds}{dv}$$ – Ng Chung Tak Jan 18 '17 at 19:08