Flash and thunder are produced simultaneously. But thunder is heard a few seconds after the flash is seen, why ?
Speed of sound is 330 m/sec in air medium at 0°C. Whereas speed of light is 3 x 108 m/sec. When we compare the speed of light with that of speed of sound, speed of light is greater than that of speed of sound. Therefore thunder is heard a few seconds after the flash is seen.
