In the diploma thesis, the motion of free fall and the projectile motion have been recorded using a high-speed camera and analysed with the Tracker software, a suitable tool for checking physical laws. A theoretical description of the drag law, is given. The change in position and velocity of a projectile, subjected to a large drag force, are determined theoretically. In the practical part, the analysis of the video clip of the free fall and the projectile motion, where the object are a plastic sphere moving through water and a balloon moving trough air, are shown. With this experiment, I check whether the drag law applies even to objects which are relatively light compared to the medium through which they move. A computer program which solves differential equations with iteration, written in the Fortran programming language, is used for computing the two-dimensional projectile motion.