Lightning
Lightning
Lightning is an electrical discharge usually, but not always, produced by well-developed thunderstorms. Although there is a clear-air lightening phenomena,light-ning most frequently occurs within a cloud (intra-cloud), between two clouds (inter-cloud), or from the cloud to the ground.
A lightning discharge can heat the air as much as five times hotter than the surface temperature of the Sun (about 54,000°F [30,000°C]). This heated air causes expansion in the air as an explosion, starting a shock wave that turns into a sound wave upon reaching the human ear. Thunder travels in all directions (radially) from the lightning at the speed of the sound approximately 738 MPH at sea level (1,188 km/h). Because it takes the sound about five seconds to travel each mile (about three seconds for 1km), the time between the lightning and the thunder can give a rough estimate of how far an observer is from a thunderstorm.
The quick flash that can be seen as lightning occurs as a complex series of events. In order to have lightning, separate regions of electrical charges must be present in a cumulonimbus cloud. There are several hypotheses as to how this occurs, one mechanism may involve falling ice particles within the cloud that transfer ions. This results in a positively charged upper part and a negatively charged middle part in the cloud. The bottom of the cloud is also mostly negatively charged, causing part of the ground underneath to become positively charged. In the insulating dry air an electrical field builds up, and when it reaches a threshold potential, the air is no longer insulating, and as a current flows, lightning occurs.
Cloud-to-ground lightning (arguably the best understood among the different types of lightning) starts inside the cloud when a critical value of the localized electric field is reached along a path, so a surge of electrons will move to the cloud base, then gradually down to the ground. A short (164 ft [50 m]) and narrow (4 in [10 cm]) conducting channel is created by ionized air molecules, which are produced by the electron flow out of the cloud. These surges of electrons move downward in a series of steps for about 164-328 ft (50-100 m), then they stop for about 50-millionths of a second, and continue for another 164 ft (50 m), creating a stepped leader form of transit. Near the ground, a current of positive charge goes up from the ground to meet the stepped leader, and when they meet, many electrons flow into the ground, and a bright return stroke moves up, following the path of the stepped leader up to the cloud, releasing heat, thunder, and charges. The subsequent leader is called the dart leader, and for subsequent flashes, the same processes reoccur in a similar cycle. Usually, a lightning flash has approximately three or four leaders, each of them accompanied by a return stroke.
I posted this little gem awhile ago: The Lightning Bug. Not sure of the origin, but my son has tied it now and then and…
… a charred image after lightning strikes. Last evening, after… commanding. I knew lightning struck very very close, because it…
… to the seashore and walked on the shoreline while I could see a suggestive lightnings storm at the skyline west coast. Just turning back to Genova round midnight, the weather…
At long last, my new musical project, The Marcos Lightning, has our new EP, "Pictures for a Living", available for …
Prevents the lightening from setting the building on fire. We ground a lot of things such as antennas. It is a common practice.Seems that the lightning bolt doe
Most things are a better conductor than air, so the lighting is trying to ground itself as fast as possible, so is searches for any object that will allow it to
the chance is slim but you cant tell if youre gonna be struck or not. One thing you can do to prevent is not to stand under a tree.ODDS OF BECOMING A LIGHTNING
the person would remain unharmed if siting in car because the charge would be transferred to the ground ’cause the car is in contact with the earth.
but if sit
Bacteria causes milk to go sour.No. It’s just that the weather conditions during a storm will cause it to sour quicker than normal.Since your grandfather could
See what it takes to film lightning…in slow motion. See All National Geographic Videos video.nationalgeographic.com
This massive clear air bolt (cloud-to-ground lightning bolt) hit about 200-250m away from our location. Here in Darwin, Australia these bolts can leap 15-20km away from the main storm striking a dry a
Video of a near-miss lightning strike in Norman, OK in July 2007, as the cloud-to-ground stroke nearly struck storm chaser Curtis McDonald. This is one of the most incredible lightning videos I have e
Ogre Battle LARPing video… No I did not film this. No I did not participate in this. No I don’t know who these people are. No I have no clue how to contact them for your tv/radio/donkey show. Yes, m
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Drawn from the life of Nikola Tesla, one of the greatest inventors of his time,
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