Video-Based Motion Analysis

Video-based motion analysis has recently become very popular in introductory physics classes. This paper outlines general recommendations regarding equipment and software; videography issues such as scaling, shutter speed, lighting, background, and camera distance; as well as other methodological aspects. Also described are the measurement and modeling of the gravitational, drag, and Magnus forces on 1) a spherical projectile undergoing one-dimensional motion and 2) a spinning spherical projectile undergoing motion within a plane. Measurement and correction methods are devised for four common, major sources of error: parallax, lens distortion, discretization, and improper scaling.