Equations of motion give us a way to model and predict the behavior of objects as they move through space as a function of time.  Kinematic equations allow us to calculate the trajectory of an object, so we can know where at will be and how it will be moving at a particular point in time.  Though describing the motion of objects is in itself important, the real power of kinematics becomes clear when we recognize how it connects to the way forces act on an object.  The connection between kinematics and dynamics is the acceleration of an object.  Forces act on an object, causing it to accelerate.  Once we know how it accelerates, we can (at least in theory) determine is motion. Alternatively, if we can use an object’s motion to determine its acceleration, we can use the acceleration to calculate how forces are acting on an object.  To truly understand an object’s motion, we want to know not just how it moves, but why it moves the way it does.  As a result, the full vector problem we are attempting to solve with mechanics requires pairing kinematics with Newton’s laws.