Final answer:
The dashed streaks of fluorescent lights observed when riding in a train are caused by the stroboscopic effect.
Step-by-step explanation:
When you are riding in a train and looking out the window, nearby fluorescent lights may appear as dashed streaks. This phenomenon is known as the 'stroboscopic effect'.
The stroboscopic effect occurs when the frequency of the light source matches or is close to the frequency at which our eyes perceive the passing objects. As a result, the objects appear as streaks or multiple images instead of a continuous motion.
The dashed streaks of fluorescent lights are caused by the relative motion between the train and the lights. As the train moves, the light rays emitted by the fluorescent lights reach our eyes at different times, creating a dashed or streaked appearance.