Is there any case/reason of not showing the directions (from negative to positive) of axes in coordinate diagrams? Sometimes I see the direction not specified, even though the discussion using that diagram assumes certain direction, which makes me confused a lot of times.
I thought it may be better to give an example domain to consider cases/reasons. In my dynamics class, I've never seen any coordinate diagrams, either 2D or 3D, with directions indicated.
Thanks.
Its a common convention , one that you are familiar since your school days. So unless and until there is a different convention being used, its assumed that all directions are according to common convention and problems are solved keeping this in mind.
However if there is a difference, as far as books i have seen , the author(s) always bring it to the notice of the reader without failure