The delay between seeing a lightning flash and hearing the thunder is due to the difference in the speed of light and sound. Light travels significantly faster than sound, so the light from the lightning reaches our eyes almost instantly, while the sound waves take a few seconds to travel the same distance.
Here’s a more detailed explanation:
Lightning Flash:
Lightning is the visible discharge of electrical energy from a cloud to the ground or within a cloud. This light travels at approximately 300,000 kilometers per second.
Thunder:
Thunder is the sound wave produced by the rapid heating and expansion of air along the path of the lightning strike. Sound travels much slower than light, typically around 343 meters per second in air.
Since the distance between the lightning strike and the observer is the same for both light and sound, the faster speed of light means it reaches our eyes before the slower-moving sound waves reach our ears, causing a delay.