Q:

Why is lighting seen before the thunder is heard?

A:

Quick Answer

Although thunder and lightning occur at the same time, the lightning is seen before the thunder is heard because light travels at a much faster speed than sound. Sound waves can also bounce off molecules in the air, causing it to travel in different directions. This accounts for the distorted rumbling sound of distant thunder while thunder that is close by can be heard as a loud crack or booming sound.

Know More

Full Answer

Lightning travels at a speed of 300,000,000 meters per second, which is about 186,000 miles per second. The speed of sound, in dry air, is about 1 mile every 5 seconds. Since dry air is not common during a thunderstorm, the speed at which thunder travels is only an approximation, but a rough calculation can still be made of the distance of a thunderstorm by comparing the time factors of lightning and its accompanying thunder. Because the speed of light is so fast, the travel time for lightning in the case of a thunderstorm's relatively close distance can be considered instantaneous. Thus, counting the elapsed time in seconds between the flash of lightning and the following thunder, and then dividing that number by 5, will provide the distance in miles. If, for example, 10 seconds pass between the lightning and the thunder, the storm is 2 miles away.

Learn More

Related Questions

  • Q:

    How do you tell how far away you are from a lighting?

    A:

    To determine how far you are from lightning, use the flash-to-bang method by counting how many seconds it takes from the moment you see the lightning to when you hear the thunder. Then divide the number of seconds by five to estimate how many miles away it is.

    Full Answer >
    Filed Under:
  • Q:

    How fast is lightning?

    A:

    A bolt of lightning travels at approximately 224,000 miles per hour or approximately 3,700 miles per second. Lightning is a discharge of static electricity that has accumulated as a result of collisions between ice particles in storm clouds.

    Full Answer >
    Filed Under:
  • Q:

    Where does thunder come from?

    A:

    Thunder comes from the rapid movement of air in a lightning bolt. Due of the speed at which lightning bolts travel, the surrounding air does not have enough time to expand. This compressed air creates a shock wave similar to an explosion, causing thunder.

    Full Answer >
    Filed Under:
  • Q:

    What is the difference between thunder and lightning?

    A:

    The difference between thunder and lightning is that lightning is electromagnetic energy and thunder is sonic energy. Lightning actually causes thunder by rapidly heating and expanding the air around the path of the strike, explains a Library of Congress website.

    Full Answer >
    Filed Under:

Explore