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How does kinematics describe motion without considering its causes?

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A diagram with labeled vector illustrations. Panel A shows vector addition with two green arrows A and B forming a parallelogram, and their sum C as a red diagonal. Panel B shows vector subtraction, with A and negative B forming resultant D. Panel C demonstrates vector components using angles and projections. Panel D uses the right-hand rule with thumbs to show the direction of the cross product E = A x B and its opposite, -E = B x A. — mechanics Figure 1: (A) The vector sum C = A + B = B + A. (B) The vector difference A + (−B) = A − B = D. (C, left) A cos θ is the component of A along B and (right) B cos θ is the component of B along A. (D, left) The right-hand rule used to find the direction of E = A × B and (right) the right-hand rule used to find the direction of −E = B × A.

Kinematics is a branch of mechanics that describes the motion of bodies or systems without considering the forces that cause that motion. By disregarding causative factors, kinematics focuses exclusively on the geometric and temporal aspects of movement.12

To describe motion, kinematics utilizes three primary variables:
* Position: The spatial location of a body or particle.1
* Velocity: The rate at which a particle's position changes over time.1
* Acceleration: The rate at which a particle's velocity changes.1

For particles moving along determinate paths, kinematics provides a mathematical description of these variables. For instance, motion along a straight path can be expressed through a list of positions at specific times or via a continuous mathematical formula. For more complex motion, such as movement along a curved path, kinematics employs position vectors to track the particle's location and calculate its velocity and acceleration relative to time. By focusing on these descriptive parameters, kinematics provides a clear, purely geometric account of how an object moves through space.13