Description of motion: specifying where an object is on a line at any given time: either drawing a graph of the position x versus time t or by giving a function x(t) for computing x from t. These equations will be used most often to describe motion throughout the course. x is the coordinate of the position. When motion in two and three dimensions is discussed, an array of coordinates are used; (x,y) or (x,y,z): r=(x,y) is the position where x and y are the coordinates. Displacement: how far away you end up at tf from where you began at ti. Velocity contains direction information compared to speed which does not. A quantity that defines magnitude and directions is called a vector: velocity is a vector, speed is not. Instantaneous velocity is the slope of the line tangent to the graph of the function x(t) This can be found through the equation below.
