AbstractThis investigation explores the conditions under which an object, moving through a liquid in high speed, has the greatest deceleration. The conditions focused on are the mass of the object, its initial velocity and its entry angle into the liquid. This is achieved through shooting pellets of varied masses and energies out of two different soft guns at a water container, recording them with a high speed camera and mapping their motion with a tracking program. The results of the experiment indicate that the lesser the mass of the object, the greater its deceleration in the fluid. The initial velocity and the entry angle of the object do not influence the rate of its speed loss. It is further explored that as the density of the fluid becomes greater, so does the deceleration of the object. The investigation is intended to deepen the understanding of the high speed motion through a medium.