Position, Velocity and Acceleration The physical quantities of position, velocity and acceleration allow us to describe the motion of objects. With these three quantities the motion of objects of all sizes from bacteria to galaxies can be understood. These three quantities are all related to each other. The instantaneous velocity vector is defined as = (1) where is the position and is the time. Similarly, the instantaneous acceleration vector is defined as = . (2) Therefore, if we make a plot of the position of an object as a function of time, the slope of this graph will give the velocity. The slope of a graph of the velocity as a function of time gives the acceleration. In this lab we will be measuring the position, velocity and acceleration of objects as a function of time using two different methods (1) rotary motion sensors and (2) video analysis. These two sections to the lab can be performed in any order as long as you complete both of them. (1) Measuring position using rotary motion sensors located in wireless carts and then finding the velocity and acceleration from these measurements. (2) Using