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).
