# Question #640ff

Apr 14, 2017

Displacement is a vector quantity whereas distance is a scalar quantity.

So imagine you run a standard 26-ish mile marathon, along any path you care for, but where the start and finishing line are the same.

If you complete the race, you have travelled a distance of 26 miles but have undergone a displacement of zero. Because you are back to where you started.

In that sense, getting back to your question, the number line is a bit like a vector quantity.

Imagine you are standing on a number line that runs East- West, and you have as the Origin where you are right now.

If you run 1 metre due West and then stop, your displacement is $+ 1 m$. if you run 1 metre due East and then stop, your displacement is $- 1 m$. Just as in the numbers on the number line.

In either case you have covered a distance of $1 m$. But on the number line, which is a 1-D vector line, you have done something that is really the opposite.