Lightning is the flash of light that occurs when charge separation occurs. Like other forms of light, the light emitted from the lightning travels near the speed of light. This speed is near 300,000,000 meters per second. Thunder is the vibration that is emitted by the rapid expansion and contraction of air. The lightning is extremely hot and during that brief time the air is superheated and expands violently. The air then cools quickly. An everyday example of a vibration in the air that produces a bang is when a balloon is filled with air until it pops. Thunder travels at the speed of sound and has a value of about 340 meters per second. The speed of sound in air at sea level moves about 1 mile every 5 seconds. Thus, when you see the lightning count the seconds and divide by 5 to get the approximate distance that the sound of thunder originates from. Note that the speed of light is much faster than the speed of thunder. When dividing the values we can determine how much faster the speed of light is. 300,000,000 / 340 = 882,353 times as fast. |