Another common choice is to use the length of the vector, which we label \(d\) (the name of the vector without the arrow on top), and the angle, \(\phi\) that the vector makes with the \(x\)-axis, as ...Another common choice is to use the length of the vector, which we label \(d\) (the name of the vector without the arrow on top), and the angle, \(\phi\) that the vector makes with the \(x\)-axis, as illustrated in Figure A1.2.1. If the vector is coming out of the page (at you!), then you would see the head of the arrow, which we represent as a circle with a dot (the dot is the point of the arrow, the circle is the base of the conically shaped arrowhead).
