# Tidying up Vectors

1. Oct 18, 2009

### Noxide

Suppose the answer to a question involving vectors is the following:

v = 42.7ms-1 at 339.4 degrees counterclockwise from the positive x-axis

Is it also correct to state the answer as

v = 42.7ms-1 at 339.4 degrees counterclockwise from R1i >= 0,

or is this representation too mathy for physics?

2. Oct 19, 2009

### lstellyl

i think you could answer it either way, though I don't think either of those answers is particularly "tidy". why is it you want to use this notation? it seems somewhat superfluous to me for the type of question it seems to be answering.

i think the most appropriate answer would depend on the context of the question, and if there was an obvious coordinate system that was specified in the question (ie, the "x axis").

IMO, the optimal way to answer it would be with a normalized cartesian vector (ie, (cos,sin)) multiplied by the velocity amplitude. and if not that, then a vector with the velocity broken up into its cartesian components.

i don't think the question is "is it too 'mathy' for physics", but rather, "is it an optimal notation to describe the situation physically, given the context"

in my experience, both mathematicians and physicists generally try to use notation that is convenient to both the writer and reader (perhaps with the exception of dirac/bra-ket notation... gah)