This video shows how to make your own strobe light using an Arduino and an LED strip. The strobe light is useful to visualize the stroboscopic effect and is much better than a strobe light app on your phone. For written instructions for the Arduino strobe light, including a circuit diagram and example code, see the Science Buddies website: https://www.sciencebuddies.org/science-fair-projects/project_ideas/Elec_p092.shtml